feat(tui): greet launch with the mark, once, drawn in braille

.agents/evidence/motion.md

@@ -6,6 +6,16 @@ resolves every one against the source, so a renamed or deleted test fails the bu
 
 | Invariant | Proven by |
 | --- | --- |
-| MOT-1 | `mot_1_one_deadline_serves_every_mover_and_late_wakes_coalesce`, `the_mark_cycle_divides_the_clock_cycle`, `effort_xhigh_labels_remain_static_without_an_animation_deadline`, `effort_animation_changes_only_visible_max_cells_and_stops_when_hidden` |
-| MOT-2 | `mot_2_every_activity_mark_frame_is_one_cell`, `effort_animation_changes_only_visible_max_cells_and_stops_when_hidden` |
+| MOT-1 | `launch_greets_once_and_leaves`, `the_first_message_ends_the_greeting_for_good`, `a_conversation_launch_did_not_greet_shows_no_mark`, `mot_1_one_deadline_serves_every_mover_and_late_wakes_coalesce`, `the_mark_cycle_divides_the_clock_cycle`, `effort_xhigh_labels_remain_static_without_an_animation_deadline`, `effort_animation_changes_only_visible_max_cells_and_stops_when_hidden` |
+| MOT-2 | `the_mark_is_braille_one_cell_a_glyph`, `mot_2_every_activity_mark_frame_is_one_cell`, `effort_animation_changes_only_visible_max_cells_and_stops_when_hidden` |
 | MOT-3 | `effort_animation_changes_only_visible_max_cells_and_stops_when_hidden` |
+
+## Rendered
+
+Launch's greeting over a new conversation, drawn by the workspace on its motion clock with
+`cargo run -p plexmaton-tui --example greeting_preview -- <directory>`: the centre grown into a
+circle at [120](../../crates/plexmaton-tui/frames/greeting/greeting-circle-120.svg), [88](../../crates/plexmaton-tui/frames/greeting/greeting-circle-88.svg) and
+[60](../../crates/plexmaton-tui/frames/greeting/greeting-circle-60.svg), and centre and frame turned at [120](../../crates/plexmaton-tui/frames/greeting/greeting-turned-120.svg),
+[88](../../crates/plexmaton-tui/frames/greeting/greeting-turned-88.svg) and [60](../../crates/plexmaton-tui/frames/greeting/greeting-turned-60.svg). The user watched it play in
+the real binary in kitty on 2026-09-23; `cargo run -p plexmaton-tui --example mark_greeting` plays
+it alone in any terminal.

.agents/phases/phase-04-product-polish.md

@@ -2,7 +2,7 @@
 
 | Field | Value |
 | --- | --- |
-| Status | Active; stages 1–9 and 11–34 complete; stage 10 branding planned and unstarted |
+| Status | Active; stages 1–34 complete; exit gate not yet assessed |
 | Parent roadmap | [Plexmaton Roadmap](../roadmap.md) |
 | Product contract | [UI/UX](../ui-ux.md) |
 | Depends on | Phase 01 interaction ownership; Phase 02 journal/accounting/budget projections; Phase 03 durable collaboration, owned child scheduling, Handoff/Stop, passive recovery and canonical Attention |
@@ -48,10 +48,11 @@ evidence file the frames and tests. Git holds how each was validated.
 9. **Composer skill picker — complete.** [SKP-1–SKP-4](../specs/composer-menu.md): `$` discovery
    above the primary input with keyboard and pointer completion; literal variables, currency and
    prose stay text.
-10. **Branding — unstarted.** The mark, a rounded-square frame around a circular centre, drawn in
-    cells at the odd size nearest square for the measured cell, first centred in an empty
-    conversation and moving on the one [motion](../specs/motion.md) clock. The
-    [stage plan](../plans/phase-04-stage-10-branding.md) owns the order.
+10. **Branding — complete.** Launch greets a new conversation with the mark once: drawn in braille,
+    a rounded-square frame around a round centre, it plays for about 2.5 s on the one
+    [motion](../specs/motion.md) clock and leaves the conversation blank (ui-ux §input). Chosen
+    in kitty from the [spike](../spikes/conversation-chrome/README.md)'s previews, after Grok's
+    braille logo; [frames](../evidence/motion.md#rendered).
 11. **Composer menu and Drawer — complete.** A Command is a slash command typed into the
     conversation it addresses ([CMC-1–CMC-3](../specs/composer-menu.md)); the Drawer, pulled by
     `Ctrl-P` ([DRW-1–DRW-4](../specs/drawer.md)), holds what outlives a Session. One

.agents/roadmap.md

@@ -34,7 +34,7 @@ table in `AGENTS.md` allows.
 | 01 | One real agent in the workspace: a thin loop over one provider, and the transcript grammar against its output | Closed 2026-09-03: delivered one live OpenAI-compatible agent, five bounded native tools with explicit approval and cancellation, and the reviewed responsive transcript grammar |
 | 02 | Canonical session state, persistence, durable permission policy, provider transports, context projection and project instructions | Closed 2026-09-12 by scoped evidence: delivered JSONL sessions and recovery, four provider dialects, compaction, durable permissions, AGENTS.md and conversation tree/rewind; unproven recovery/readmission acceptance inherited by Phase 03, independent export/import by Phase 04; MCP optional |
 | 03 | Durable multi-agent mailbox and runtime ownership | Closed 2026-09-16: delivered ordered durable delegation/mail, owned child scheduling, Stop and Handoff control, passive, process-kill and in-app switch recovery, canonical Attention and the accepted responsive agent workspace |
-| 04 | Product polish, performance hardening, math in production, and extensibility | Active; stages 1–9 and 11–34 complete; stage 10 branding planned and unstarted |
+| 04 | Product polish, performance hardening, math in production, and extensibility | Active; stages 1–34 complete; exit gate not yet assessed |
 
 ## Locked
 

.agents/specs/motion.md

@@ -2,10 +2,10 @@
 
 | Field | Value |
 | --- | --- |
-| Status | Implemented for the effort rail and the activity line's mark |
+| Status | Implemented for the effort rail, the activity line's mark and launch's greeting |
 | Owns | When anything in the workspace moves, what a moving frame may change, and the one clock it runs on |
 | Depends on | FR-1 and FR-3 in [frame-loop](./frame-loop.md); EFF-4 in [reasoning-effort](./reasoning-effort.md) as the first thing that moves |
-| Proven by | `plexmaton-tui::workspace` effort tests and `plexmaton-tui::render` activity-mark tests |
+| Proven by | `plexmaton-tui::workspace` effort and greeting tests and `plexmaton-tui::render` activity-mark and mark tests |
 
 ## Invariants
 
@@ -28,3 +28,7 @@ clock was doing.
 The phase is a count, not a time: renderers derive their frame from it, so two moving things on
 screen stay in step. The effort rail's marker and the activity line's mark each complete a cycle every
 1.6 s, the mark over seven frames holding unequal numbers of its 24 phases.
+
+Launch's greeting is not a cycle. It counts the clock's phases from the instant launch greeted,
+plays its 38 once (ui-ux §input), and then, or at the conversation's first entry, stops for good
+and wakes the clock no more; the braille mark it draws is one cell a glyph (MOT-2).

.agents/spikes/conversation-chrome/README.md

@@ -3,13 +3,13 @@
 | Field | Value |
 | --- | --- |
 | Question | How the working agent, the user's turn and the mark should look, decided from rendered candidates |
-| Feeds | [Phase 04](../../phases/phase-04-product-polish.md) stage 34, complete, and the [stage 10](../../plans/phase-04-stage-10-branding.md) plan |
+| Feeds | [Phase 04](../../phases/phase-04-product-polish.md) stages 34 and 10, both complete |
 | Method | HTML mockups in the palette, opened for the user; two kitty scripts for what a browser cannot show |
 
 Every decision below was made by the user on a rendered frame, 2026-09-21 and 2026-09-22. The
 generators are in [`mockups/`](./mockups/); each writes one HTML page to
 `plexmaton-conversation-chrome/` under the system temporary directory, outside this corpus, and
-`spin.py`, `mark-lively.py`, `logo_term.py` and `cellsize.py` run in a terminal. Regenerate rather than trusting a description of them.
+`spin.py`, `mark-lively.py`, `mark-braille.py`, `mark-braille-frame.py`, `logo_term.py` and `cellsize.py` run in a terminal. Regenerate rather than trusting a description of them.
 
 ## What the user chose
 
@@ -18,9 +18,10 @@ generators are in [`mockups/`](./mockups/); each writes one HTML page to
 | Activity line composition | mark, label, muted `· 32s · high effort`, `· quiet for 31s` once nothing has arrived; no token count | a red stall tell; estimated tokens |
 | Activity mark | H: a dot grows into a circle, turns into a rounded square and a square, spins into a diamond and shrinks away through a smaller one, lingering on whole shapes, 1.6 s a cycle; chosen 2026-09-23 in kitty (`mark-lively.py`) after the user found N2 rigid and wanted it to grow from a point | N2, the circle, rounded square and square outline then filled, chosen 2026-09-22 and later found rigid; one size changing shape, and even steps retracing their path, likewise; a slice-by-slice sweep, which reads as progress; C2′ and C2″, which shook because mixed-size Unicode shapes centre differently; filled squares; braille; quarter circles; Claude Code's star |
 | User message | band of lifted ground with a blue `›`, continuation indented | the accent bar; a bare prefix; a hairline bar; a band alone |
-| Mark placement | centred in the empty conversation, name beneath, gone with the first message | a header or drawer slot, not yet asked for |
-| Mark motion | K4 as the base: frame breathes between weights and drifts between palette slots; centre morphs circle, ring, rounded square, square, solid and outline | K1 to K3 as they stood |
-| Mark glyphs | the Material Design family the Nerd Font carries, one cell each, drawn together so they centre together | Unicode geometric shapes from mixed blocks, which jump between fallback fonts |
+| Mark placement | a greeting: at launch onto an empty conversation it plays once at the centre, name beneath, and leaves after about 2.5 s: frame fades in for 0.25 s, the F3 cycle runs in 2 s with one 0.8 s sheen, frame and name fade out in 0.3 s; chosen 2026-09-23 after the user asked for it to be less aggressive and quicker | staying and moving until the first message, too insistent; 3.7 s, too slow; a header or drawer slot, not yet asked for |
+| Mark drawing | braille, the way Grok draws its logo: two by four dots a cell, a rounded-square frame around a round centre as one small bitmap, square once corrected for the terminal's cell; chosen 2026-09-23 (`mark-braille.py`) | box drawing at three weights around a one-cell Nerd Font centre, which the user found too coarse to look good at any size |
+| Mark motion | F3: the centre grows from a dot into a circle, becomes a rounded square and a square, turns into a diamond while the frame turns with it, and shrinks away, 3.2 s a cycle; Grok's sheen sweeps it every 4 s; chosen 2026-09-23 (`mark-braille-frame.py`) after the user asked for the outside to move as well as the inside | the frame breathing and drifting through palette slots (F1); frame and centre in counterpoint (F2); all of it at once (F4); K4's shape-only morph, rigid |
+| Activity mark glyphs | the Material Design family the Nerd Font carries, one cell each, drawn together so they centre together | Unicode geometric shapes from mixed blocks, which jump between fallback fonts |
 
 The activity indicator and the mark are two things: the row has one cell, the empty conversation
 has a block. They share the clock and the glyph family, not the geometry.
@@ -60,3 +61,4 @@ the family's, so they cannot join its cycle; `▢`, `◼` and `⬤` are not in t
 | Stall | glyph and verb fade to red after 3 s without tokens | | phase timer never resets on payload churn |
 | User turn | band, subtle `❯`, no hanging indent, text colour unchanged | band blended 12 % toward white from the real terminal background, dim `›`, two-space indent, never truncated | band, accent `❯`, indent, folds past three lines |
 | Clock | one shared interval, halved when the window is blurred, off when scrolled away | | demand-driven; idle parks with no wakeups; every frame unit-tested to one column |
+| Logo | | | braille art at seven or five rows by window height, none below; a sheen sweeps bottom-left to top-right in 1.3 s of every 4, over a slow pulse, redrawn at 12 fps |

.agents/spikes/conversation-chrome/mockups/mark-braille-frame.py

@@ -0,0 +1,124 @@
+#!/usr/bin/env python3
+"""The braille mark with the frame moving too, around the centre that grows and turns. Ctrl-C to stop."""
+import math, sys, time
+
+sys.path.insert(0, __import__("os").path.dirname(__file__))
+base = __import__("mark-braille")  # noqa: E402
+
+DRIFT = [(130, 180, 240), (139, 92, 246), (217, 70, 239), (139, 92, 246), (130, 180, 240), (120, 210, 205)]
+CYCLE = 3.2
+ease = lambda k: 0.5 - 0.5 * math.cos(math.pi * max(0.0, min(1.0, k)))
+
+
+def drift(t, period=4.8):
+    x = (t / period * len(DRIFT)) % len(DRIFT)
+    i = int(x)
+    return base.mix(DRIFT[i], DRIFT[(i + 1) % len(DRIFT)], x - i)
+
+
+def phase(t):
+    return (t % CYCLE) / CYCLE
+
+
+def squareness(t):
+    """0 while the centre is a circle, 1 once it has become a square (follows growing_core)."""
+    p = phase(t)
+    if p < 0.30:
+        return 0.0
+    if p < 0.48:
+        return ease((p - 0.30) / 0.18)
+    return 1.0 if p < 0.84 else 1.0 - ease((p - 0.84) / 0.16)
+
+
+def turned(t):
+    """0 upright, 1 turned a quarter of a right angle further (the diamond), following the centre."""
+    p = phase(t)
+    if p < 0.60:
+        return 0.0
+    if p < 0.78:
+        return ease((p - 0.60) / 0.18)
+    return 1.0 if p < 0.84 else 1.0 - ease((p - 0.84) / 0.16)
+
+
+def frame(t, breathe=False, counterpoint=False, turn=False):
+    """(inside-the-ring test, colour) for the frame at time t."""
+    thickness = 0.075
+    if breathe:
+        thickness = 0.05 + 0.06 * (0.5 - 0.5 * math.cos(math.tau * t / 1.6))
+    radius = 0.36
+    if counterpoint:
+        radius = 0.20 + 0.66 * squareness(t)  # square-ish around a circle, a circle around a square
+    angle = turned(t) * math.pi / 4 if turn else 0.0
+    scale = 1.0 / (1.0 + (math.sqrt(2) - 1.0) * math.sin(angle * 2) ** 2) if turn else 1.0
+    half = 0.9 * scale
+
+    def ring(x, y):
+        c, s = math.cos(angle), math.sin(angle)
+        x, y = x * c + y * s, -x * s + y * c
+        return abs(base.rounded_box(x, y, half, min(radius, half))) < thickness
+    return ring
+
+
+def draw(mark, core, ring, frame_ink, shine=None):
+    lines = []
+    w, h = mark.cols * 2, mark.rows * 4
+    cx, cy = w * mark.dw / 2, h * mark.dh / 2
+    for row in range(mark.rows):
+        line = ""
+        for col in range(mark.cols):
+            bits, frame_dots, core_dots = 0, 0, 0
+            for dy in range(4):
+                for dx in range(2):
+                    px = ((col * 2 + dx + 0.5) * mark.dw - cx) / mark.half
+                    py = ((row * 4 + dy + 0.5) * mark.dh - cy) / mark.half
+                    on_ring, inside = ring(px, py), core(px, py)
+                    if on_ring or inside:
+                        bits |= base.DOTS[dy][dx]
+                        frame_dots += on_ring
+                        core_dots += inside and not on_ring
+            ink = frame_ink if frame_dots >= core_dots else base.PURPLE
+            if shine:
+                ink = base.mix(ink, base.TEXT, shine(col, row, mark.cols, mark.rows))
+            line += f"\x1b[38;2;{ink[0]};{ink[1]};{ink[2]}m{chr(0x2800 + bits)}" if bits else " "
+        lines.append(line + "\x1b[0m")
+    return lines
+
+
+CANDIDATES = [
+    ("F1  the frame breathes and drifts, with the sheen", lambda t: (frame(t, breathe=True), drift(t), base.grok_shine(t))),
+    ("F2  inside and outside in counterpoint, with the sheen", lambda t: (frame(t, counterpoint=True), base.BLUE, base.grok_shine(t))),
+    ("F3  they turn together, with the sheen", lambda t: (frame(t, turn=True), base.BLUE, base.grok_shine(t))),
+    ("F4  all of it: breathe, drift, counterpoint, turn, sheen", lambda t: (frame(t, True, True, True), drift(t), base.grok_shine(t))),
+]
+
+
+def main():
+    cell = base.cell_px()
+    marks = [base.Mark(7, cell), base.Mark(5, cell)]
+    print(f"\n  cell {cell[0]:.1f}×{cell[1]:.1f} px; marks {marks[0].cols}×7 and {marks[1].cols}×5 cells\n")
+    height = 7 + 3
+    sys.stdout.write("\x1b[?25l")
+    start = time.time()
+    try:
+        while True:
+            t = math.floor((time.time() - start) * base.FPS) / base.FPS
+            core = base.growing_core(t)
+            for name, make in CANDIDATES:
+                ring, ink, shine = make(t)
+                blocks = [draw(m, core, ring, ink, shine) for m in marks]
+                for row in range(7):
+                    small = blocks[1][row - 1] if 1 <= row <= 5 else " " * marks[1].cols
+                    sys.stdout.write(f"    {blocks[0][row]}      {small}\x1b[K\n")
+                name_row = f"\x1b[38;2;230;233;240m{'Plexmaton':^{marks[0].cols}}\x1b[0m"
+                sys.stdout.write(f"    {name_row}      \x1b[38;2;142;162;196m{name}\x1b[0m\x1b[K\n\n\n")
+            sys.stdout.write(f"\x1b[{height * len(CANDIDATES)}A")
+            sys.stdout.flush()
+            time.sleep(1 / base.FPS / 2)
+    except KeyboardInterrupt:
+        pass
+    finally:
+        sys.stdout.write(f"\x1b[{height * len(CANDIDATES)}B\x1b[?25h\x1b[0m\n")
+
+
+if __name__ == "__main__":
+    main()