[daropotter]

What

Adds kitty support to opencode-terminal-progress, gated on kitty 0.47+ — the version that
draws an in-window progress bar (progress_bar option in kitty.conf) and shows the state
indicator in the tab title.

Detection & version gate

if (env['KITTY_WINDOW_ID'] || env['TERM_PROGRAM'] === 'kitty') {
  const version = await detectKittyVersion();
  if (version && isSupportedKitty(version)) return 'kitty';
  return undefined;
}

• KITTY_WINDOW_ID is set by kitty itself for every process it launches (also without shell
  integration / when TERM_PROGRAM is missing) — the kitty equivalent of ITERM_SESSION_ID /
  WEZTERM_EXECUTABLE.
• The version is read from TERM_PROGRAM_VERSION (shell integration) or, on Linux, by resolving the
  running emulator binary via /proc/<KITTY_PID>/exe and running --version. If the version cannot
  be confirmed as ≥ 0.47, the plugin stays a no-op.

setup is async (await detectTerminal()) — allowed by Plugin.Definition.

Keeping the kitty indicator alive

kitty auto-clears any OSC 9;4 progress ~60 s after the last report (clear_timeout in
kitty/kitty/progress.py), so a single report per state change made the indicator vanish during
longer runs. While a state is active the plugin now re-reports it every 30 s — only on kitty, and
with the same canonical payload: busy 9;4;3 (indeterminate), waiting 9;4;4;50, error 9;4;2,
idle 9;4;0. No determinate 9;4;1;N sequences are emitted; busy stays indeterminate, matching
the canonical ConEmu/OSC 9;4 semantics and the visuals of the other supported terminals
(Windows Terminal, Ghostty, WezTerm, VTE, iTerm2 render indeterminate as a spinner/pulse).

Checks

• tsc --noEmit ✅ · ESLint ✅ · bun build ✅
• e2e (mock context, OSC captured via pty): a 31 s busy emits 9;4;3 per heartbeat with no
  9;4;1;N; waiting emits 4;50, error 2, idle 0.
• Live on kitty 0.49.2 (Linux): the tab-state indicator stays visible for over 60 s, pauses at
  50 % on questions, clears on idle.