Round-2 review fixes validation

Base reviewed: c67c15e

$ npx vitest run test/goals-flow.test.ts test/intercom.test.ts
2 files passed; 68 tests passed.
Note: the test harness deliberately executes one negative git preflight outside a repository, which prints `fatal: not a git repository` to stderr.

$ env -u PI_SUBAGENT_CHILD -u PI_GOALS_ROLE PI_GOALS_EVIDENCE_DIR=/tmp/pi-goals-round-2-XUrKAl npm test
22 files passed; 161 tests passed.

$ env -u PI_SUBAGENT_CHILD -u PI_GOALS_ROLE npm run typecheck
Passed (tsc --noEmit).

$ env -u PI_SUBAGENT_CHILD -u PI_GOALS_ROLE npm run lint
Passed (Biome checked 42 files; no fixes applied).

$ env -u PI_SUBAGENT_CHILD -u PI_GOALS_ROLE npm run build
Passed (tsc).

$ git diff --check
Passed.
