P2.1 + P3.1: Agent skeleton and CLI skeleton

Agent (P2.1): Agent struct with registry DB, runtime, and logger.
gRPC server with TLS 1.3 and MCIAS auth interceptor. Graceful
shutdown on SIGINT/SIGTERM. All RPCs return Unimplemented until
handlers are built in P2.2-P2.9.

CLI (P3.1): Full command tree with all 15 subcommands as stubs
(login, deploy, stop, start, restart, list, ps, status, sync,
adopt, service show/edit/export, push, pull, node list/add/remove).
gRPC dial helper with TLS, CA cert, and bearer token attachment.

Both gates for parallel Phase 2+3 work are now open.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

PROGRESS_V1.md

@@ -15,7 +15,7 @@
 
 ## Phase 2: Agent
 
-- [ ] **P2.1** Agent skeleton and gRPC server
+- [x] **P2.1** Agent skeleton and gRPC server
 - [ ] **P2.2** Deploy handler
 - [ ] **P2.3** Lifecycle handlers (stop, start, restart)
 - [ ] **P2.4** Status handlers (list, live check, get status)
@@ -27,7 +27,7 @@
 
 ## Phase 3: CLI
 
-- [ ] **P3.1** CLI skeleton
+- [x] **P3.1** CLI skeleton
 - [ ] **P3.2** Login command
 - [ ] **P3.3** Deploy command
 - [ ] **P3.4** Lifecycle commands (stop, start, restart)