[mhmdibrahimm]

Summary

Implements Trello card #30 · M4 Persistent lobby lifecycle + host migration.

• adds persistent PostgreSQL-backed lobby create, join, configure, start, leave, and close behavior
• runs the live lobby through a Nakama-authoritative match while retaining durable lobby, membership, configuration, and host-assignment state
• validates host ownership and the expected lobby version on every host command
• migrates host ownership transactionally when the current host leaves or disconnects
• adds a Unity development panel for the two-player lifecycle and migration check
• pins the repository Unity MCP editor dependency used to compile and validate the client integration
• extends the realtime smoke test to cover two scoped players, lifecycle state, disconnect migration, stale-version rejection, and migrated-host authority

The start request records an accepted lobby transition; round creation and gameplay state remain scoped to card #31.

Validation

• npm run verify
• Go vet, unit tests, and race tests
• two-player NestJS → Nakama bridge/lobby smoke test
• Unity script compilation with zero errors
• Unity Play Mode offline bootstrap smoke check
• Unity 6000.3.18f1 WebGL development build (Build Finished, Result: Success)

Test notes

The credential-bearing two-client visual check is documented in clients/unity/README.md. Development WebGL builds containing a temporary access token must remain local and must not be deployed.

[mcfarhat]

@mohammadibrahim3 Approved & merging — excellent first M4 deliverable. ✅ Server-authoritative lobby, host always re-derived from the open host-assignment row with per-command ownership + version rechecks, transactional disconnect-driven host migration, WAX-only, least-privilege, no secrets. Node build/typecheck/tests + all 5 CI jobs green (incl. Go -race, Postgres, and the two-player migration smoke test). Great work.