Add Phase 12 server AI semantic accounting layer

app/modules/accounting/bank_ui.py

@@ -9,7 +9,7 @@ from app.core.db.common import CommonSessionLocal
 from app.core.security.csrf import get_or_create_csrf_token, validate_csrf
 from app.core.templating import templates
 from app.modules.accounting.bank_service import (
-    confirm_review, import_completed_job, preflight_choices, queue_post, queue_preflight,
+    ai_assist_transaction, confirm_review, import_completed_job, preflight_choices, queue_post, queue_preflight,
     queue_rows, sync_posting, visible_workstations,
 )
 from app.modules.accounting.ledger_learning_service import active_natures
@@ -121,3 +121,37 @@ def post(request: Request, tx_id: int, client_id: int = Form(...), bank_ledger_n
     except Exception as exc:
         db.rollback(); return _go(client_id, error=str(exc))
     finally: db.close()
+
+
+@router.post("/{tx_id}/ai-assist")
+def ai_assist(
+    request: Request,
+    tx_id: int,
+    client_id: int = Form(...),
+    csrf_token: str = Form(...),
+):
+    validate_csrf(request, csrf_token)
+    db = CommonSessionLocal()
+    try:
+        user, denied = _require_partner(request, db, "accounting.learning.manage")
+        if denied:
+            return denied
+        client, _, scope = _find_visible_client(db, request, user, client_id)
+        if not client:
+            return _go(error="Client is not visible.")
+        decision = ai_assist_transaction(
+            db,
+            tx_id=tx_id,
+            tenant_id=scope.tenant_id,
+            client_id=client.id,
+            user_id=user.id,
+        )
+        return _go(
+            client.id,
+            message=f"AI semantic fallback completed at {decision.combined_confidence}% combined confidence.",
+        )
+    except Exception as exc:
+        db.rollback()
+        return _go(client_id, error=str(exc))
+    finally:
+        db.close()