feat(CF-536): Integrate comprehensive Sentry into task-mcp

- Create sentry.ts with MCP-aware initialization and PII scrubbing
- Replace basic inline Sentry initialization with initSentry()
- Update .env.vault-mapping for sentry.backend-node.dsn secret
- Includes PostgreSQL integration and transaction tracing

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

src/index.ts

@@ -13,22 +13,15 @@
 import dotenv from 'dotenv';
 import { fileURLToPath } from 'url';
 import { dirname, join } from 'path';
-import * as Sentry from '@sentry/node';
 
 const __filename = fileURLToPath(import.meta.url);
 const __dirname = dirname(__filename);
 const envPath = join(__dirname, '..', '.env');
 const result = dotenv.config({ path: envPath, override: true });
 
-// Initialize Sentry for error tracking
-if (process.env.SENTRY_DSN) {
-  Sentry.init({
-    dsn: process.env.SENTRY_DSN,
-    environment: process.env.SENTRY_ENVIRONMENT || 'production',
-    tracesSampleRate: parseFloat(process.env.SENTRY_API_TRACE_RATE || '0.1'),
-    integrations: [Sentry.postgresIntegration()],
-  });
-}
+// Initialize Sentry for error tracking (with MCP-aware filtering and PII scrubbing)
+import { initSentry } from './sentry.js';
+initSentry(process.env.SENTRY_ENVIRONMENT || 'production');
 
 // Log environment loading status (goes to MCP server logs)
 if (result.error) {