Clean reimplement orchestrator bootstrap prompt loading

[fujiwaranosai850]

Summary

• reimplement orchestrator bootstrap prompt loading with winner-takes-all fallback
• inject only the resolved source as orchestrator.md for real main sessions
• add regression and E2E coverage for fallback order, topic-aware resolution, and non-orchestrator exclusion

Testing

• npx tsx --test lib/dispatch/bootstrap-hook.test.ts lib/services/bootstrap.e2e.test.ts

Notes

• npm run check still reports unrelated pre-existing repo type/dependency errors outside this change set

[fujiwaranosai850]

Closing as superseded. This older #190 lane was replaced by the accepted #195/#197 promotion path, which landed in devclaw-local-current and was exported upstream as laurentenhoor#541.