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/prisma/seed.ts

@@ -340,7 +340,8 @@ pnpm prisma migrate deploy
 \`\`\`
 
 For setup instructions, see [[development-setup]].`,
-        summary: "Comprehensive documentation of the Mosaic Stack database schema and Prisma conventions",
+        summary:
+          "Comprehensive documentation of the Mosaic Stack database schema and Prisma conventions",
         status: EntryStatus.PUBLISHED,
         visibility: Visibility.WORKSPACE,
         tags: ["architecture", "development"],
@@ -373,7 +374,7 @@ This is a draft document. See [[architecture-overview]] for current state.`,
 
     // Create entries and track them for linking
     const createdEntries = new Map<string, any>();
-    
+
     for (const entryData of entries) {
       const entry = await tx.knowledgeEntry.create({
         data: {
@@ -388,7 +389,7 @@ This is a draft document. See [[architecture-overview]] for current state.`,
           updatedBy: user.id,
         },
       });
-      
+
       createdEntries.set(entryData.slug, entry);
 
       // Create initial version
@@ -406,7 +407,7 @@ This is a draft document. See [[architecture-overview]] for current state.`,
 
       // Add tags
       for (const tagSlug of entryData.tags) {
-        const tag = tags.find(t => t.slug === tagSlug);
+        const tag = tags.find((t) => t.slug === tagSlug);
         if (tag) {
           await tx.knowledgeEntryTag.create({
             data: {
@@ -427,7 +428,11 @@ This is a draft document. See [[architecture-overview]] for current state.`,
       { source: "welcome", target: "database-schema", text: "database-schema" },
       { source: "architecture-overview", target: "development-setup", text: "development-setup" },
       { source: "architecture-overview", target: "database-schema", text: "database-schema" },
-      { source: "development-setup", target: "architecture-overview", text: "architecture-overview" },
+      {
+        source: "development-setup",
+        target: "architecture-overview",
+        text: "architecture-overview",
+      },
       { source: "development-setup", target: "database-schema", text: "database-schema" },
       { source: "database-schema", target: "architecture-overview", text: "architecture-overview" },
       { source: "database-schema", target: "development-setup", text: "development-setup" },
@@ -437,7 +442,7 @@ This is a draft document. See [[architecture-overview]] for current state.`,
     for (const link of links) {
       const sourceEntry = createdEntries.get(link.source);
       const targetEntry = createdEntries.get(link.target);
-      
+
       if (sourceEntry && targetEntry) {
         await tx.knowledgeLink.create({
           data: {