feat(pi): bundle codebase-analyzer persona with scoped runtime config

[danievanzyl]

Closes #101

Summary

• bundle Pi-native codebase-analyzer for local read-only reconnaissance
• validate/apply persona thinking and inheritSkills runtime defaults
• isolate child Pi extension lifecycle; harden shutdown handling
• document precedence; add discovery, dispatch, packaging, and lifecycle regression coverage

Validation

• bun test tests/subagents/index.test.ts tests/subagents/personas.test.ts — 10 pass, 0 fail, 23 assertions
• Pi extension typecheck — pass
• full eval/hooks/sync-skills feedback loop — pass
• npm pack --dry-run --json assertion — includes extensions/subagents/agents/codebase-analyzer.md
• pi --approve --no-extensions -e . --list-models — pass
• real delegated RPC smoke — gpt-5.6-luna, exit 0, exact file:line evidence, no inherited skills, unchanged git status --short

Dispatch verification

shepard-tests: DISCOVERED=1 RAN=1 PASS=1 FAIL=0 sha=1d25f61 ASSERTIONS=14 APASS=14 AFAIL=0

Ran scripts/run-tests.sh --ledger /tmp/code-skills-101-review-head.ledger at PR head 1d25f61 and compared it with the same runner's /tmp/code-skills-101-base.ledger from PR base 275c961161eead65e9175101cfdec6476625047d.

diff -u /tmp/code-skills-101-base.ledger /tmp/code-skills-101-review-head.ledger is empty: zero new FAIL records; TEST assertions 14 → 14 (no decrease).

[danievanzyl]

Review — CHANGES MADE

Findings resolved

• [P1] Child extension leakage: delegated Pi processes still discovered unrelated extensions. With the package installed, the real analyzer smoke loaded package lifecycle hooks and exited 1 after producing its report. Children now use --no-extensions; the repeated RPC smoke exits 0 with accurate file:line evidence, gpt-5.6-luna, no inherited skills, and unchanged git status.
• [P1] Shutdown race: background completion/rejection callbacks updated the status event bus after session_shutdown, causing a stale-context exception. Both callbacks now stop before touching extension context.
• [P2] Acceptance coverage gaps: added exact bundled runtime-argument coverage, both directions of explicit inheritSkills precedence, invalid-value sibling retention, shutdown regression coverage, and an npm-pack assertion for the bundled persona.

No unresolved findings.

Validation

• Subagent tests: 10 pass, 0 fail, 23 assertions
• Pi extension typecheck: pass
• Package contents + package load: pass
• Eval suite: 152 pass, 0 fail; eval typecheck: pass
• Hook + sync-skills feedback loop: all green
• Required ledger diff vs 275c961161eead65e9175101cfdec6476625047d: empty; 0 new FAIL, assertions 14 → 14
• CI validate: pass

Review commit: 1d25f6146bc00ecc52483314c0b2c19c63ca4a57

[danievanzyl]

REGRESSION-FOUND

shepard-survey: SURFACES=8 PROBED=8 FINDINGS=1 sha=1d25f6146bc00ecc52483314c0b2c19c63ca4a57

• Regression — existing personas lose extension-provided runtime support (extensions/subagents/index.ts:114): every child now receives --no-extensions. Before this diff, children discovered configured extensions, so existing personas could use extension-registered model providers, built-in tool overrides, and runtime hooks. A persona pinned to an extension-registered model now starts without that provider and cannot run. Failing coverage committed in fbe750a; no fix included.

Consumed PR evidence: shepard-tests: DISCOVERED=1 RAN=1 PASS=1 FAIL=0 sha=1d25f61 ASSERTIONS=14 APASS=14 AFAIL=0.