feat: operator-only test-rung route to verify a rung works

[mabry1985]

Problem

Companion to protoAgent#1749 (coder.solve()'s new force_rung). Verifying fusion (rung 4) actually works required contriving a task hard enough to fail greedy, best-of-k, and tree-search first before fusion is even reached — impractical for a quick sanity check.

Fix

POST /api/plugins/project_board/features/{id}/test-rung — runs exactly ONE named rung (greedy/best-of-k/tree-search/fusion) against a feature's real acceptance tests, in a throwaway worktree that's always reaped — never promoted, no PR opened, no board state touched.

POST /api/plugins/project_board/features/bd-7/test-rung
{"rung": "fusion"}

→ {"rung": "fusion", "passed": true, "gens_spent": 2, "candidates_tried": 2, "note": "...", "verdict_output": "3 passed in 0.4s"}

coder_seam.test_rung() is deliberately separate from dispatch() — that function's contract (promote the winner, raise SolveExhausted on exhaustion) is shaped for the board's real per-feature build; mixing test semantics into it would risk the real dispatch path.

Where this does NOT go — no @tool wrapper

Deliberately kept off the agent-facing tool surface. This repo already draws exactly this boundary: board_create_feature/board_mark_ready/board_list/board_retro/board_create_epic are the only 5 @tool-wrapped functions the board's own lead agent can call — /features/{id}/cancel and DELETE /features/{id} are HTTP-only, operator-reachable, with no tool. test-rung follows the same rule: the board's own lead agent has no way to call it.

Refactor

Extracted loop.py's _resolve_delegate into coder_seam.resolve_delegate (module-level) so the new route and the real dispatch path share one lookup instead of two copies.

Tests

269 passed (was 260; +9 in test_coder_seam.py for test_rung's always-reap/pass/fail/exception/fusion-forwarding behavior, +9 in test_api.py for the route's validation gates — unknown rung, unknown feature, no acceptance criteria, no coder plugin, no test command, missing delegate, missing fusion delegate — plus the happy path and a 400-not-500 on a solve() failure).

Gate: ruff check . && ruff format --check . && pytest -q — all green.

Version bumped 0.28.0 → 0.29.0 (new capability).

🤖 Generated with Claude Code

[protoquinn]

👀 Quinn is reviewing — verdict (PASS / WARN / FAIL) + findings to follow.

[protoquinn]

QA Audit — PR #65 | feat: operator-only test-rung route to verify a rung works

VERDICT: WARN (preliminary — CI still queued; no blocking findings from diff review)

---

CI Status

• test: queued ⏳ — terminal verdict deferred until CI completes

Diff Review

• New POST /features/{fid}/test-rung route with comprehensive validation gates (rung whitelist, feature existence, acceptance criteria, coder plugin, test command, delegate resolution) — clean and consistent with existing cancel/delete boundary
• resolve_delegate() extracted from loop.py into coder_seam.py as a module-level function — eliminates duplication between dispatch and test-rung paths. Clean
• test_rung() in coder_seam.py has an explicit always-reap contract. The full implementation body is truncated in the diff summary, so the always-reap logic (worktree cleanup, no promotion) could not be line-by-line verified — see Gap below

Observations

• LOW: clawpatch structural review unavailable (HTTP 502 on checkout cache). Diff-based review only
• MEDIUM/Gap: full test_rung() body and new test files (test_coder_seam.py +9, test_api.py +9) were truncated beyond the 200-line diff limit. The always-reap logic, _solve/_budget_cls plumbing, and test assertions were not line-by-line reviewed. Author claims 269 passing tests — CI will confirm
• No HIGH or CRITICAL findings from the visible diff. The except Exception → HTTP 400 pattern is deliberate and appropriate for a diagnostic endpoint that wraps an unpredictable coder.solve() call
• The @tool-wrapper exclusion is correctly applied — consistent with /cancel and DELETE /features/{id}

— Quinn, QA Engineer

[protoquinn]

Submitted COMMENT review on #65.