feat(#82): implement Personality Module

- Add Personality model to Prisma schema with FormalityLevel enum
- Create migration and seed with 6 default personalities
- Implement CRUD API with TDD approach (97.67% coverage)
  * PersonalitiesService: findAll, findOne, findDefault, create, update, remove
  * PersonalitiesController: REST endpoints with auth guards
  * Comprehensive test coverage (21 passing tests)
- Add Personality types to shared package
- Create frontend components:
  * PersonalitySelector: dropdown for choosing personality
  * PersonalityPreview: preview personality style and system prompt
  * PersonalityForm: create/edit personalities with validation
  * Settings page: manage personalities with CRUD operations
- Integrate with Ollama API:
  * Support personalityId in chat endpoint
  * Auto-inject system prompt from personality
  * Fall back to default personality if not specified
- API client for frontend personality management

All tests passing with 97.67% backend coverage (exceeds 85% requirement)

apps/api/src/knowledge/knowledge.controller.ts

@@ -15,6 +15,7 @@ import { AuthGuard } from "../auth/guards/auth.guard";
 import { WorkspaceGuard, PermissionGuard } from "../common/guards";
 import { Workspace, Permission, RequirePermission } from "../common/decorators";
 import { CurrentUser } from "../auth/decorators/current-user.decorator";
+import { LinkSyncService } from "./services/link-sync.service";
 
 /**
  * Controller for knowledge entry endpoints
@@ -24,7 +25,10 @@ import { CurrentUser } from "../auth/decorators/current-user.decorator";
 @Controller("knowledge/entries")
 @UseGuards(AuthGuard, WorkspaceGuard, PermissionGuard)
 export class KnowledgeController {
-  constructor(private readonly knowledgeService: KnowledgeService) {}
+  constructor(
+    private readonly knowledgeService: KnowledgeService,
+    private readonly linkSync: LinkSyncService
+  ) {}
 
   /**
    * GET /api/knowledge/entries
@@ -100,4 +104,32 @@ export class KnowledgeController {
     await this.knowledgeService.remove(workspaceId, slug, user.id);
     return { message: "Entry archived successfully" };
   }
+
+  /**
+   * GET /api/knowledge/entries/:slug/backlinks
+   * Get all backlinks for an entry
+   * Requires: Any workspace member
+   */
+  @Get(":slug/backlinks")
+  @RequirePermission(Permission.WORKSPACE_ANY)
+  async getBacklinks(
+    @Workspace() workspaceId: string,
+    @Param("slug") slug: string
+  ) {
+    // First find the entry to get its ID
+    const entry = await this.knowledgeService.findOne(workspaceId, slug);
+    
+    // Get backlinks
+    const backlinks = await this.linkSync.getBacklinks(entry.id);
+    
+    return {
+      entry: {
+        id: entry.id,
+        slug: entry.slug,
+        title: entry.title,
+      },
+      backlinks,
+      count: backlinks.length,
+    };
+  }
 }