feat: implement audit logging system with service, controller, and interceptor to track user actions across core services

src/connection-requests/connection-requests.service.ts

@@ -9,12 +9,15 @@ import { EventEmitter2 } from '@nestjs/event-emitter';
 import { PrismaService } from '../prisma/prisma.service';
 import { ConnectionStatus } from '@prisma/client';
 import { CreateConnectionRequestDto, RespondConnectionRequestDto } from './dto';
+import { AuditService } from '../audit/audit.service';
+import { AuditAction } from '../audit/audit.constants';
 
 @Injectable()
 export class ConnectionRequestsService {
   constructor(
     private prisma: PrismaService,
     private eventEmitter: EventEmitter2,
+    private audit: AuditService,
   ) {}
 
   /**
@@ -320,6 +323,16 @@ export class ConnectionRequestsService {
       connectionRequestId: requestId,
     });
 
+    this.audit.log({
+      action:
+        dto.status === ConnectionStatus.ACCEPTED
+          ? AuditAction.CONNECTION_REQUEST_ACCEPT
+          : AuditAction.CONNECTION_REQUEST_REJECT,
+      resourceType: 'ConnectionRequest',
+      resourceId: requestId,
+      metadata: { userId: request.userId, agentProfileId },
+    });
+
     return updated;
   }
 
@@ -385,9 +398,22 @@ export class ConnectionRequestsService {
       throw new BadRequestException('Only pending or accepted connections can be removed');
     }
 
-    return this.prisma.connectionRequest.delete({
+    const deleted = await this.prisma.connectionRequest.delete({
       where: { id: requestId },
     });
+
+    this.audit.log({
+      action: AuditAction.CONNECTION_REQUEST_CANCEL,
+      resourceType: 'ConnectionRequest',
+      resourceId: requestId,
+      metadata: {
+        userId: request.userId,
+        agentProfileId: request.agentProfileId,
+        previousStatus: request.status,
+      },
+    });
+
+    return deleted;
   }
 
   /**