Major changes:
- Add TSS core library (pkg/tss) with keygen and signing protocols
- Implement gRPC clients for Server Party service
- Add MPC session endpoints to Account service
- Deploy 3 Server Party instances in docker-compose
- Add MarkPartyReady and StartSession to proto definitions
- Complete integration tests for 2-of-3, 3-of-5, 4-of-7 thresholds
- Add comprehensive documentation (architecture, API, testing, deployment)
Test results:
- 2-of-3: PASSED (keygen 93s, signing 80s)
- 3-of-5: PASSED (keygen 198s, signing 120s)
- 4-of-7: PASSED (keygen 221s, signing 150s)
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>