feat: Warnfenster und Planungs-Hinweis bei möglicher Doppelzählung (A12-T4)

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

finance/app/routers/gui.py

@@ -27,6 +27,7 @@ from app.routers.planning import recurring_suggestions as _recurring_suggestions
 from app.routers.scenarios import list_scenarios as _list_scenarios
 from app.routers.transactions import count_transactions, list_transactions, normalize_sort
 from app.services.balances import account_balance, total_balance
+from app.services.double_count import all_conflicts
 from app.services.planning_chart import refresh_planning_chart
 from app.services.projection_service import refresh_stale_projections
 from app.version import get_version
@@ -337,6 +338,11 @@ def planung_page(request: Request, session: Session = Depends(get_session)):
     recurring = _list_recurring(session=session)
     planned = _list_planned(session=session)
     loans = _list_loans(session=session)
+    doppelt_posten: dict[int, list[str]] = {}
+    doppelt_kredit: dict[int, list[str]] = {}
+    for k in all_conflicts(session):
+        doppelt_posten.setdefault(k.posten_id, []).append(k.kredit_name)
+        doppelt_kredit.setdefault(k.kredit_id, []).append(k.posten_name)
     return templates.TemplateResponse(request, "planning.html", {
         "categories": categories,
         "category_names": {c.id: c.name for c in categories},
@@ -347,6 +353,8 @@ def planung_page(request: Request, session: Session = Depends(get_session)):
         "loans": loans,
         "rhythms": ["monthly", "quarterly", "yearly"],
         "repayment_types": ["annuity", "bullet"],
+        "doppelt_posten": doppelt_posten,
+        "doppelt_kredit": doppelt_kredit,
     })