plugin-loader conformance suite: Statement-mismatch, wrong-kind (every kind), undeclared-need and cross-instance connection RED arms

[MattJackson]

What

From the loader-PL1 audit: the published conformance suite lacked the RED arms §2 requires of every plugin. This adds three, and turns the wrong-kind arm (which ran only in the store script) into an arm every kind carries. They live in crates/plugin-loader/src/conformance/red.rs and conformance_suite! emits them for every plugin. Each drives the plugin's own door into the misbehaviour, requires the host to refuse it, and keeps an honest twin that must pass beside it.

test (emitted by conformance_suite!)	the misbehaving plugin	required refusal	honest twin
red_a_statement_other_than_the_stated_one_is_refused	the door under a linked row and a signed manifest stating a rendering one byte off; the door restated with another version under its honest row	StatementMismatch, linked and dropped in	the honest door loads linked and dropped in
red_a_door_asked_for_as_another_kind_is_refused	the door asked for as each of the six kinds it is not	WrongKind linked, ManifestKind dropped in (before dlopen)	loads as its own kind, both ways
red_a_connection_over_an_undeclared_need_is_refused	the door's instance (restated with one outbound need, bound over the suite's test table) calling ESTABLISH on its own context for need 1 and for the highest need index, neither ever declared	REFUSED, the plugin did not declare this need	its declared need 0 opens to a loopback listener
red_another_instances_connection_is_refused	a second instance of the door, on the same table, calling WRITE, READ and CLOSE on the first instance's connection	each REFUSED, the connection belongs to another plugin instance	the owner writes before and after, then closes

The connection arms call the host's connector slots (CONN_SLOTS) on the instance's own context. These are the calls a plugin makes through the tables open hands it, so the arm exercises the host's per-instance identity and need checks exactly as a plugin meets them.

The store script's own refused as another kind step stays as it was (its fold is unchanged).

Loader-side tests (conformance_suite_tests.rs, module red_arms)

• GREEN: an honest door of two kinds (the plane fixture plane_door_plugin and the hook fixture hook_door) passes all four arms, linked and dropped in.
• RED: a plugin whose dropped-in library is not its linked door (the plane door shipped with the hook library) fails the Statement arm and the kind arm, on their honest twins.

Neutrality and the kind-isolation matrix

with_a_tcp_need is renamed with_an_outbound_need, and the connection fixture reuses Subject::conns (the suite's own test table) rather than naming the table type again. So this PR adds no kind-isolation matrix hit and removes two: 13919 on base, 13917 here. No plane, dialect or vendor noun was added.

plugin-ci.yml

It is left unchanged. Its suite list names the tests every plugin must RUN green, and plugin repos call the workflow against older pins that lack these four. Every test in the conformance target still has to pass in that step (the cargo test run fails the step on any failure), so the arms bite every plugin whose pin includes them. Adding the four names to the required list is a one-line change once the fleet's pins carry this commit.

Checks (Latchkey, large)

check	job	result
cargo xtask gate --all --format=tsv, base predev 5e672d125 vs head 91474ad24, tags in the bundle	cli-7e34bff7-582c-4129-8ebc-be4d00bc0353 / cli-b63d09e5-c9b2-4786-998e-ffb846eb862c	GATE EXIT 1 on both (base carries 12 FAIL rows). 556 judged rows; verdict columns identical (541 PASS / 12 FAIL / 3 EXCUSED); non-PASS rows byte-identical; kind-isolation matrix 13919 -> 13917
fmt; workspace clippy -D warnings; instance-noun-neutrality, kind-isolation, plane-purity, structure-lint selftests	cli-f766c2fd-02e8-4053-804c-375d33edc64c	all rc 0
loader conformance:: tests (CI=1, the loader's examples built)	cli-08289c11-2080-404f-9538-55217414598e	42 passed, 0 failed (the red_arms GREEN and RED among them)
loader lib, all	same	641 passed, 2 failed: the two secret both-ways tests that need busbar_secret_env_plugin's cdylib from another crate, which this job does not build (unchanged from base)
busbar-plane-decisions suite, release, BUSBAR_EXPECT_RELEASE=1	same	13/13 ok, the four new arms included; the RED count run rc 101 on the comparator (Linked: step 'facts': 0 crossing(s), pinned 1)

No oracle cell, golden or replay input is touched, so there is no oracle proof to state.

[github-actions]

promote into predev: all green @b88ac57d8

Already red on predev, not this PR's: 11

gate	row	detail
construction	one-pick-site	3 production call site(s) of 'pick_among(' (ceiling 2): crates/busbar-kernel-egress/src/walk.rs:298; crates/busbar-llm/src/engine/exhaustion/fallback.rs:120; crates/busbar-llm/src/engine/pipeline.rs:8
kind-isolation	kind-isolation:deps	3 finding(s), 93 shipped edge instance(s) over 30 class(es), 93 declaration(s); 56 '[[dep]]' row(s), 0 question(s): unlisted-dep-edge legacy -> plane busbar-llm -> busbar-plane-llm is a shipped edge w
kind-isolation	kind-isolation:test-deps	3 finding(s), 35 test edge instance(s) over 21 class(es), 35 declaration(s); 20 '[[dep]]' row(s), 0 question(s): unlisted-dep-edge cleanliness -> legacy busbar-core-admin -> busbar-a2a is a test edge
kind-isolation	kind-isolation:law0	9 hit(s) off the [[law0]] ceilings, 5 finding(s) over 14 neutral crate(s): law0-rise busbar × instance:secret 37 hit(s) against a ceiling of 35: this landing grew a neutral crate's instance vocabulary
kind-isolation-ship	kind-isolation:deps	10 finding(s) over 93 shipped edge(s): ship-edge kernel -> hooks busbar-kernel -> busbar-hook-ranking is 'not-allowed': the architecture grants no kernel -> hooks edge, and the ship criterion is the a
kind-isolation-ship	kind-isolation:test-deps	10 finding(s) over 35 test edge(s): ship-edge cleanliness -> export busbar-core-admin -> busbar-export-prometheus is 'not-allowed': the architecture grants no cleanliness -> export edge, and the ship
kind-isolation-ship	kind-isolation:law0	9 hit(s) off the [[law0]] ceilings, 5 finding(s) over 14 neutral crate(s): law0-rise busbar × instance:secret 37 hit(s) against a ceiling of 35: this landing grew a neutral crate's instance vocabulary
kind-isolation-ship	kind-isolation:faces	2 finding(s) over 40 crate(s): foreign-entry crates/busbar busbar is kind 'root' and implements 'Transport' 1 time(s) in shipped source — the entry face of kind 'transport'. A trait implementation is
kind-isolation-ship	kind-isolation:legacy-drain	3 finding(s): transitional-live qa/kind-isolation.toml 'busbar-a2a -> busbar-core-admin' (legacy drain: the retiring A2A engine's tests drive the admin surface that drained into the cleanliness tier)
ship-ready	ship-ready:ship-twin	'kind-isolation-ship' is not green: kind-isolation:deps (a dependency the architecture does not grant is still in the graph); kind-isolation:test-deps (a dependency the architecture does not grant is
structure-lint	structure-lint:plane-dup:unledgered	22 finding(s): PLANE-DUPLICATE (module): 'config.rs' — a2a:crates/busbar-a2a/src/a2a/config.rs decisions:crates/busbar-plane-decisions/src/config.rs voice:crates/busbar-voice/src/config.rs (the ledger

tests passed: 20973, failed: 0. Run: https://github.com/GetBusbar/busbar/actions/runs/38221322339 . Artifact verdict-b88ac57d824eaec69f82554d33b59b57e6a18345 (failures.json, junit.xml, raw.log; 90 days).