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>

apps/api/src/prisma/prisma.service.spec.ts

@@ -23,9 +23,7 @@ describe("PrismaService", () => {
 
   describe("onModuleInit", () => {
     it("should connect to the database", async () => {
-      const connectSpy = vi
-        .spyOn(service, "$connect")
-        .mockResolvedValue(undefined);
+      const connectSpy = vi.spyOn(service, "$connect").mockResolvedValue(undefined);
 
       await service.onModuleInit();
 
@@ -42,9 +40,7 @@ describe("PrismaService", () => {
 
   describe("onModuleDestroy", () => {
     it("should disconnect from the database", async () => {
-      const disconnectSpy = vi
-        .spyOn(service, "$disconnect")
-        .mockResolvedValue(undefined);
+      const disconnectSpy = vi.spyOn(service, "$disconnect").mockResolvedValue(undefined);
 
       await service.onModuleDestroy();
 
@@ -62,9 +58,7 @@ describe("PrismaService", () => {
     });
 
     it("should return false when database is not accessible", async () => {
-      vi
-        .spyOn(service, "$queryRaw")
-        .mockRejectedValue(new Error("Database error"));
+      vi.spyOn(service, "$queryRaw").mockRejectedValue(new Error("Database error"));
 
       const result = await service.isHealthy();
 
@@ -100,9 +94,7 @@ describe("PrismaService", () => {
     });
 
     it("should return connected false when query fails", async () => {
-      vi
-        .spyOn(service, "$queryRaw")
-        .mockRejectedValue(new Error("Query failed"));
+      vi.spyOn(service, "$queryRaw").mockRejectedValue(new Error("Query failed"));
 
       const result = await service.getConnectionInfo();