chore: ajoute ruff (lint) et corrige les violations

- Config ruff dans pyproject.toml : règles E/W/F/I/UP/B, whitelist des appels
  d'injection FastAPI (Depends/File/Form/Query) pour B008, B904 ignoré
  (traduction volontaire des exceptions en réponses HTTP)
- Auto-fixes : tri des imports, suppression d'imports inutilisés, annotations
  PEP 604, f-strings sans placeholder, modes open redondants
- Suppression de variables inutilisées (config.reset_setting, parser locataires)

ruff check . : All checks passed ; 61 tests OK

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/plesna_gerance/api/routes/dashboard.py

@@ -1,21 +1,21 @@
 """Dashboard routes - Aggregated data for the home page."""
 
-from datetime import date, timedelta
 from collections import defaultdict
+from datetime import date, timedelta
 
 from fastapi import APIRouter, Depends
-from sqlalchemy.orm import Session
-from sqlalchemy import select, func, desc
 from pydantic import BaseModel
+from sqlalchemy import desc, func, select
+from sqlalchemy.orm import Session
 
 from ...database import get_session
 from ...database.models import (
+    Depense,
     Document,
     Immeuble,
-    Lot,
     Locataire,
+    Lot,
     Revenu,
-    Depense,
 )
 
 router = APIRouter(prefix="/api/dashboard", tags=["dashboard"])