fix: replace Python 3.10+ union type syntax with typing.Optional for Pydantic v2 compat

from __future__ import annotations breaks Pydantic BaseModel runtime type
evaluation. Replaced str | None → Optional[str], list[str] → List[str] etc.
in control_generator.py, anchor_finder.py, control_generator_routes.py.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend-compliance/compliance/services/control_generator.py

@@ -17,8 +17,6 @@ Three License Rules:
   Rule 3 (restricted):       BSI, ISO — full reformulation, no source names
 """
 
-from __future__ import annotations
-
 import hashlib
 import json
 import logging
@@ -27,7 +25,7 @@ import re
 import uuid
 from dataclasses import dataclass, field, asdict
 from datetime import datetime, timezone
-from typing import Optional
+from typing import Dict, List, Optional, Set
 
 import httpx
 from pydantic import BaseModel
@@ -168,8 +166,8 @@ def _detect_domain(text: str) -> str:
 # ---------------------------------------------------------------------------
 
 class GeneratorConfig(BaseModel):
-    collections: list[str] | None = None
-    domain: str | None = None
+    collections: Optional[List[str]] = None
+    domain: Optional[str] = None
     batch_size: int = 5
     max_controls: int = 50
     skip_processed: bool = True
@@ -194,9 +192,9 @@ class GeneratedControl:
     release_state: str = "draft"
     tags: list = field(default_factory=list)
     # 3-rule fields
-    license_rule: int | None = None
-    source_original_text: str | None = None
-    source_citation: dict | None = None
+    license_rule: Optional[int] = None
+    source_original_text: Optional[str] = None
+    source_citation: Optional[dict] = None
     customer_visible: bool = True
     generation_metadata: dict = field(default_factory=dict)
 
@@ -219,7 +217,7 @@ class GeneratorResult:
 # LLM Client (via Go SDK)
 # ---------------------------------------------------------------------------
 
-async def _llm_chat(prompt: str, system_prompt: str | None = None) -> str:
+async def _llm_chat(prompt: str, system_prompt: Optional[str] = None) -> str:
     """Call the Go SDK LLM chat endpoint."""
     messages = []
     if system_prompt:
@@ -322,11 +320,11 @@ Antworte NUR mit validem JSON."""
 class ControlGeneratorPipeline:
     """Orchestrates the 7-stage control generation pipeline."""
 
-    def __init__(self, db: Session, rag_client: ComplianceRAGClient | None = None):
+    def __init__(self, db: Session, rag_client: Optional[ComplianceRAGClient] = None):
         self.db = db
         self.rag = rag_client or get_rag_client()
-        self._existing_controls: list[dict] | None = None
-        self._existing_embeddings: dict[str, list[float]] = {}
+        self._existing_controls: Optional[List[dict]] = None
+        self._existing_embeddings: Dict[str, List[float]] = {}
 
     # ── Stage 1: RAG Scan ──────────────────────────────────────────────
 
@@ -537,7 +535,7 @@ Gib JSON zurück mit diesen Feldern:
 
     # ── Stage 4: Harmonization ─────────────────────────────────────────
 
-    async def _check_harmonization(self, new_control: GeneratedControl) -> list | None:
+    async def _check_harmonization(self, new_control: GeneratedControl) -> Optional[list]:
         """Check if a new control duplicates existing ones via embedding similarity."""
         existing = self._load_existing_controls()
         if not existing:
@@ -698,7 +696,7 @@ Gib JSON zurück mit diesen Feldern:
         except Exception as e:
             logger.error("Failed to update job: %s", e)
 
-    def _store_control(self, control: GeneratedControl, job_id: str) -> str | None:
+    def _store_control(self, control: GeneratedControl, job_id: str) -> Optional[str]:
         """Persist a generated control to DB. Returns the control UUID or None."""
         try:
             # Get framework UUID
@@ -889,7 +887,7 @@ Gib JSON zurück mit diesen Feldern:
         chunk: RAGSearchResult,
         config: GeneratorConfig,
         job_id: str,
-    ) -> GeneratedControl | None:
+    ) -> Optional[GeneratedControl]:
         """Process a single chunk through stages 2-5."""
         # Stage 2: License classification
         license_info = self._classify_license(chunk)