refactor(backend/api): extract DSR services (Step 4 — file 15 of 18)

compliance/api/dsr_routes.py (1176 LOC) -> 369 LOC thin routes +
469-line DsrService + 487-line DsrWorkflowService + 101-line schemas.

Two-service split for Data Subject Request (DSGVO Art. 15-22):
  - dsr_service.py: CRUD, list, stats, export, audit log
  - dsr_workflow_service.py: identity verification, processing,
    portability, escalation

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

backend-compliance/compliance/schemas/dsr.py

@@ -0,0 +1,101 @@
+"""
+DSR (Data Subject Request) schemas — Betroffenenanfragen nach DSGVO Art. 15-21.
+
+Phase 1 Step 4: extracted from ``compliance.api.dsr_routes``.
+"""
+
+from typing import Any, Dict, List, Optional
+
+from pydantic import BaseModel
+
+
+class DSRCreate(BaseModel):
+    request_type: str = "access"
+    requester_name: str
+    requester_email: str
+    requester_phone: Optional[str] = None
+    requester_address: Optional[str] = None
+    requester_customer_id: Optional[str] = None
+    source: str = "email"
+    source_details: Optional[str] = None
+    request_text: Optional[str] = None
+    priority: Optional[str] = "normal"
+    notes: Optional[str] = None
+
+
+class DSRUpdate(BaseModel):
+    priority: Optional[str] = None
+    notes: Optional[str] = None
+    internal_notes: Optional[str] = None
+    assigned_to: Optional[str] = None
+    request_text: Optional[str] = None
+    affected_systems: Optional[List[str]] = None
+    erasure_checklist: Optional[List[Dict[str, Any]]] = None
+    rectification_details: Optional[Dict[str, Any]] = None
+    objection_details: Optional[Dict[str, Any]] = None
+
+
+class StatusChange(BaseModel):
+    status: str
+    comment: Optional[str] = None
+
+
+class VerifyIdentity(BaseModel):
+    method: str
+    notes: Optional[str] = None
+    document_ref: Optional[str] = None
+
+
+class AssignRequest(BaseModel):
+    assignee_id: str
+
+
+class ExtendDeadline(BaseModel):
+    reason: str
+    days: Optional[int] = 60
+
+
+class CompleteDSR(BaseModel):
+    summary: Optional[str] = None
+    result_data: Optional[Dict[str, Any]] = None
+
+
+class RejectDSR(BaseModel):
+    reason: str
+    legal_basis: Optional[str] = None
+
+
+class SendCommunication(BaseModel):
+    communication_type: str = "outgoing"
+    channel: str = "email"
+    subject: Optional[str] = None
+    content: str
+    template_used: Optional[str] = None
+
+
+class UpdateExceptionCheck(BaseModel):
+    applies: bool
+    notes: Optional[str] = None
+
+
+class CreateTemplateVersion(BaseModel):
+    version: str = "1.0"
+    language: Optional[str] = "de"
+    subject: str
+    body_html: str
+    body_text: Optional[str] = None
+
+
+__all__ = [
+    "DSRCreate",
+    "DSRUpdate",
+    "StatusChange",
+    "VerifyIdentity",
+    "AssignRequest",
+    "ExtendDeadline",
+    "CompleteDSR",
+    "RejectDSR",
+    "SendCommunication",
+    "UpdateExceptionCheck",
+    "CreateTemplateVersion",
+]