feat(#93): implement agent spawn via federation

Implements FED-010: Agent Spawn via Federation feature that enables
spawning and managing Claude agents on remote federated Mosaic Stack
instances via COMMAND message type.

Features:
- Federation agent command types (spawn, status, kill)
- FederationAgentService for handling agent operations
- Integration with orchestrator's agent spawner/lifecycle services
- API endpoints for spawning, querying status, and killing agents
- Full command routing through federation COMMAND infrastructure
- Comprehensive test coverage (12/12 tests passing)

Architecture:
- Hub → Spoke: Spawn agents on remote instances
- Command flow: FederationController → FederationAgentService →
  CommandService → Remote Orchestrator
- Response handling: Remote orchestrator returns agent status/results
- Security: Connection validation, signature verification

Files created:
- apps/api/src/federation/types/federation-agent.types.ts
- apps/api/src/federation/federation-agent.service.ts
- apps/api/src/federation/federation-agent.service.spec.ts

Files modified:
- apps/api/src/federation/command.service.ts (agent command routing)
- apps/api/src/federation/federation.controller.ts (agent endpoints)
- apps/api/src/federation/federation.module.ts (service registration)
- apps/orchestrator/src/api/agents/agents.controller.ts (status endpoint)
- apps/orchestrator/src/api/agents/agents.module.ts (lifecycle integration)

Testing:
- 12/12 tests passing for FederationAgentService
- All command service tests passing
- TypeScript compilation successful
- Linting passed

Refs #93

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

ISSUES/29-cron-config.md

@@ -1,11 +1,13 @@
 # Cron Job Configuration - Issue #29
 
 ## Overview
+
 Implement cron job configuration for Mosaic Stack, likely as a MoltBot plugin for scheduled reminders/commands.
 
 ## Requirements (inferred from CLAUDE.md pattern)
 
 ### Plugin Structure
+
 ```
 plugins/mosaic-plugin-cron/
 ├── SKILL.md          # MoltBot skill definition
@@ -15,17 +17,20 @@ plugins/mosaic-plugin-cron/
 ```
 
 ### Core Features
+
 1. Create/update/delete cron schedules
 2. Trigger MoltBot commands on schedule
 3. Workspace-scoped (RLS)
 4. PDA-friendly UI
 
 ### API Endpoints (inferred)
+
 - `POST /api/cron` - Create schedule
 - `GET /api/cron` - List schedules
 - `DELETE /api/cron/:id` - Delete schedule
 
 ### Database (Prisma)
+
 ```prisma
 model CronSchedule {
   id          String   @id @default(uuid())
@@ -41,11 +46,13 @@ model CronSchedule {
 ```
 
 ## TDD Approach
+
 1. **RED** - Write tests for CronService
 2. **GREEN** - Implement minimal service
 3. **REFACTOR** - Add CRUD controller + API endpoints
 
 ## Next Steps
+
 - [ ] Create feature branch: `git checkout -b feature/29-cron-config`
 - [ ] Write failing tests for cron service
 - [ ] Implement service (Green)