feat: phase 5 - implement automatic drift detection and recovery for node reconnection

feat: phase 4 - browser and shell skill integration with synchronized workspace

feat: implement workspace mirroring phase 3 - ignore filters and locking

feat: implement real-time multi-agent workspace sync (Phase 1 & 2)

docs: correct implementation plan status for Phase 4 & 5; refactor: implement shutdown for ShellSkill

fix(agent): implement graceful shutdown for browser processes and fix SkillManager capacity cleanup

refactor(poc-grpc): restructure project into modular 12-factor architecture with dedicated orchestrator and agent_node packages