Add Phase 12 server AI semantic accounting layer

app/modules/accounting/purchase_review_ui.py

@@ -11,7 +11,7 @@ from app.modules.accounting.historical_learning_service import active_natures
 from app.modules.accounting.ledger_learning_service import available_tally_guids
 from app.modules.accounting.purchase_review_service import (
     review_queue, review_counts, return_periods, nature_maps_for_rows,
-    explanations_for_rows, mappings_by_nature, review_one, bulk_confirm,
+    explanations_for_rows, mappings_by_nature, review_one, bulk_confirm, ai_assist_one,
 )
 from app.modules.accounting.ui import _find_visible_client, _require_partner, _visible_clients
 from app.modules.core.rbac.deps import get_user_permissions, get_user_roles
@@ -90,3 +90,52 @@ async def bulk_confirm_rows(request:Request):
     except Exception as exc:
         db.rollback(); return _redirect(client_id,filters,error=str(exc))
     finally:db.close()
+
+
+@router.post("/purchase/{purchase_id}/ai-assist")
+def ai_assist_purchase_row(
+    request: Request,
+    purchase_id: int,
+    client_id: int = Form(...),
+    tally_guid: str = Form(""),
+    status: str = Form("all"),
+    confidence: str = Form("all"),
+    source: str = Form("all"),
+    supplier: str = Form(""),
+    return_period: str = Form(""),
+    page: int = Form(1),
+    per_page: int = Form(25),
+    csrf_token: str = Form(...),
+):
+    validate_csrf(request, csrf_token)
+    db = CommonSessionLocal()
+    filters = {
+        "tally_guid": tally_guid, "status": status, "confidence": confidence,
+        "source": source, "supplier": supplier, "return_period": return_period,
+        "page": page, "per_page": per_page,
+    }
+    try:
+        user, response = _require_partner(request, db, "accounting.learning.manage")
+        if response:
+            return response
+        client, _, scope = _find_visible_client(db, request, user, client_id)
+        if not client:
+            from app.core.http_responses import ui_access_denied
+            return ui_access_denied()
+        decision = ai_assist_one(
+            db,
+            tenant_id=scope.tenant_id,
+            client_id=client.id,
+            purchase_id=purchase_id,
+            user_id=user.id,
+        )
+        return _redirect(
+            client.id,
+            filters,
+            message=f"AI semantic fallback completed at {decision.combined_confidence}% combined confidence.",
+        )
+    except Exception as exc:
+        db.rollback()
+        return _redirect(client_id, filters, error=str(exc))
+    finally:
+        db.close()