feat: add comprehensive performance benchmark tracking system

- Create benchmark test suites for critical operations:
  - Node loading performance
  - Database query performance
  - Search operations performance
  - Validation performance
  - MCP tool execution performance

- Add GitHub Actions workflow for benchmark tracking:
  - Runs on push to main and PRs
  - Uses github-action-benchmark for historical tracking
  - Comments on PRs with performance results
  - Alerts on >10% performance regressions
  - Stores results in GitHub Pages

- Create benchmark infrastructure:
  - Custom Vitest benchmark configuration
  - JSON reporter for CI results
  - Result formatter for github-action-benchmark
  - Performance threshold documentation

- Add supporting utilities:
  - SQLiteStorageService for benchmark database setup
  - MCPEngine wrapper for testing MCP tools
  - Test factories for generating benchmark data
  - Enhanced NodeRepository with benchmark methods

- Document benchmark system:
  - Comprehensive benchmark guide in docs/BENCHMARKS.md
  - Performance thresholds in .github/BENCHMARK_THRESHOLDS.md
  - README for benchmarks directory
  - Integration with existing test suite

The benchmark system will help monitor performance over time and catch regressions before they reach production.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

src/services/sqlite-storage-service.ts

@@ -0,0 +1,86 @@
+/**
+ * SQLiteStorageService - A simple wrapper around DatabaseAdapter for benchmarks
+ */
+import { DatabaseAdapter, createDatabaseAdapter } from '../database/database-adapter';
+
+export class SQLiteStorageService {
+  private adapter: DatabaseAdapter | null = null;
+  private dbPath: string;
+
+  constructor(dbPath: string = ':memory:') {
+    this.dbPath = dbPath;
+    this.initSync();
+  }
+
+  private initSync() {
+    // For benchmarks, we'll use synchronous initialization
+    // In real usage, this should be async
+    const Database = require('better-sqlite3');
+    const db = new Database(this.dbPath);
+    
+    // Create a simple adapter
+    this.adapter = {
+      prepare: (sql: string) => db.prepare(sql),
+      exec: (sql: string) => db.exec(sql),
+      close: () => db.close(),
+      pragma: (key: string, value?: any) => db.pragma(`${key}${value !== undefined ? ` = ${value}` : ''}`),
+      inTransaction: db.inTransaction,
+      transaction: (fn: () => any) => db.transaction(fn)(),
+      checkFTS5Support: () => {
+        try {
+          db.exec("CREATE VIRTUAL TABLE test_fts USING fts5(content)");
+          db.exec("DROP TABLE test_fts");
+          return true;
+        } catch {
+          return false;
+        }
+      }
+    };
+    
+    // Initialize schema
+    this.initializeSchema();
+  }
+  
+  private initializeSchema() {
+    const schema = `
+      CREATE TABLE IF NOT EXISTS nodes (
+        node_type TEXT PRIMARY KEY,
+        package_name TEXT NOT NULL,
+        display_name TEXT NOT NULL,
+        description TEXT,
+        category TEXT,
+        development_style TEXT CHECK(development_style IN ('declarative', 'programmatic')),
+        is_ai_tool INTEGER DEFAULT 0,
+        is_trigger INTEGER DEFAULT 0,
+        is_webhook INTEGER DEFAULT 0,
+        is_versioned INTEGER DEFAULT 0,
+        version TEXT,
+        documentation TEXT,
+        properties_schema TEXT,
+        operations TEXT,
+        credentials_required TEXT,
+        updated_at DATETIME DEFAULT CURRENT_TIMESTAMP
+      );
+      
+      CREATE INDEX IF NOT EXISTS idx_package ON nodes(package_name);
+      CREATE INDEX IF NOT EXISTS idx_ai_tool ON nodes(is_ai_tool);
+      CREATE INDEX IF NOT EXISTS idx_category ON nodes(category);
+    `;
+    
+    this.adapter!.exec(schema);
+  }
+
+  get db(): DatabaseAdapter {
+    if (!this.adapter) {
+      throw new Error('Database not initialized');
+    }
+    return this.adapter;
+  }
+
+  close() {
+    if (this.adapter) {
+      this.adapter.close();
+      this.adapter = null;
+    }
+  }
+}