fix: fehlende SessionLocal, HTTPException, text Imports in canonical_control_routes

SessionLocal: 5x verwendet fuer DB-Sessions ausserhalb Depends()
HTTPException: verwendet in Framework-Validation
text: 55x verwendet fuer raw SQL queries

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend-compliance/compliance/api/canonical_control_routes.py

@@ -27,11 +27,12 @@ import json
 import logging
 from typing import Any, Optional
 
-from fastapi import APIRouter, Depends, Query
+from fastapi import APIRouter, Depends, HTTPException, Query
+from sqlalchemy import text
 from sqlalchemy.orm import Session
 from pydantic import BaseModel
 
-from classroom_engine.database import get_db
+from classroom_engine.database import get_db, SessionLocal
 from compliance.api._http_errors import translate_domain_errors
 from compliance.schemas.canonical_control import (
     ControlCreateRequest,