fix: resolve SQL parsing for triggers in schema initialization

**Issue**: 30 CI tests failing with "incomplete input" database error
- tests/unit/mcp/get-node-essentials-examples.test.ts (16 tests)
- tests/unit/mcp/search-nodes-examples.test.ts (14 tests)

**Root Cause**:
Both `src/mcp/server.ts` and `tests/integration/database/test-utils.ts`
used naive `schema.split(';')` to parse SQL statements. This breaks
trigger definitions containing semicolons inside BEGIN...END blocks:

```sql
CREATE TRIGGER nodes_fts_insert AFTER INSERT ON nodes
BEGIN
  INSERT INTO nodes_fts(...) VALUES (...);  -- ← semicolon inside block
END;
```

Splitting by ';' created incomplete statements, causing SQLite parse errors.

**Fix**:
- Added `parseSQLStatements()` method to both files
- Tracks `inBlock` state when entering BEGIN...END blocks
- Only splits on ';' when NOT inside a block
- Skips SQL comments and empty lines
- Preserves complete trigger definitions

**Documentation**:
Added clarifying comments to explain FTS5 search architecture:
- `NodeRepository.searchNodes()`: Legacy LIKE-based search for direct repository usage
- `MCPServer.searchNodes()`: Production FTS5 search used by ALL MCP tools

This addresses confusion from code review where FTS5 appeared unused.
In reality, FTS5 IS used via MCPServer.searchNodes() (lines 1189-1203).

**Verification**:
✅ get-node-essentials-examples.test.ts: 16 tests passed
✅ search-nodes-examples.test.ts: 14 tests passed
✅ CI database validation: 25 tests passed
✅ Build successful with no TypeScript errors

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

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

tests/integration/database/test-utils.ts

@@ -103,18 +103,64 @@ export class TestDatabase {
 
     const schemaPath = path.join(__dirname, '../../../src/database/schema.sql');
     const schema = fs.readFileSync(schemaPath, 'utf-8');
-    
-    // Execute schema statements one by one
-    const statements = schema
-      .split(';')
-      .map(s => s.trim())
-      .filter(s => s.length > 0);
+
+    // Parse SQL statements properly (handles BEGIN...END blocks in triggers)
+    const statements = this.parseSQLStatements(schema);
 
     for (const statement of statements) {
       this.db.exec(statement);
     }
   }
 
+  /**
+   * Parse SQL statements from schema file, properly handling multi-line statements
+   * including triggers with BEGIN...END blocks
+   */
+  private parseSQLStatements(sql: string): string[] {
+    const statements: string[] = [];
+    let current = '';
+    let inBlock = false;
+
+    const lines = sql.split('\n');
+
+    for (const line of lines) {
+      const trimmed = line.trim().toUpperCase();
+
+      // Skip comments and empty lines
+      if (trimmed.startsWith('--') || trimmed === '') {
+        continue;
+      }
+
+      // Track BEGIN...END blocks (triggers, procedures)
+      if (trimmed.includes('BEGIN')) {
+        inBlock = true;
+      }
+
+      current += line + '\n';
+
+      // End of block (trigger/procedure)
+      if (inBlock && trimmed === 'END;') {
+        statements.push(current.trim());
+        current = '';
+        inBlock = false;
+        continue;
+      }
+
+      // Regular statement end (not in block)
+      if (!inBlock && trimmed.endsWith(';')) {
+        statements.push(current.trim());
+        current = '';
+      }
+    }
+
+    // Add any remaining content
+    if (current.trim()) {
+      statements.push(current.trim());
+    }
+
+    return statements.filter(s => s.length > 0);
+  }
+
   /**
    * Gets the underlying better-sqlite3 database instance.
    * @throws Error if database is not initialized