feat: add clients nomenclator, order edit/delete/devalidate, invoice types, dashboard redesign

- New clients table with PF/PJ support, fiscal data (CUI, IBAN, eFactura fields)
- Full CRUD API for clients with search, sync integration
- Order lifecycle: edit header (DRAFT), devalidate (VALIDAT→DRAFT), delete order/invoice
- Invoice types: FACTURA (B2B) vs BON_FISCAL (B2C) with different nr formats
- OrderCreateView redesigned as multi-step flow (client→vehicle→details)
- Autocomplete from catalog_norme/catalog_preturi in OrderLineForm
- Dashboard now combines stats + full orders table with filter tabs and search
- ClientPicker and VehiclePicker with inline creation capability
- Frontend schema aligned with backend (missing columns causing sync errors)
- Mobile responsive fixes for OrderDetailView buttons

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/api-contract.json

@@ -21,7 +21,7 @@
       "headers": {"Authorization": "Bearer <token>"},
       "response": {
         "tables": {
-          "vehicles": [], "orders": [], "order_lines": [],
+          "clients": [], "vehicles": [], "orders": [], "order_lines": [],
           "invoices": [], "appointments": [],
           "catalog_marci": [], "catalog_modele": [],
           "catalog_ansamble": [], "catalog_norme": [],
@@ -42,12 +42,22 @@
   },
   "orders": {
     "GET /orders": {"response": [{"id": "str", "status": "str", "nr_auto": "str", "total_general": 0}]},
-    "POST /orders": {"body": {"vehicle_id": "str", "tip_deviz_id": "str", "km_intrare": 0, "observatii": "str"}, "response": {"id": "str"}},
+    "POST /orders": {"body": {"vehicle_id": "str", "client_id": "str", "tip_deviz_id": "str", "km_intrare": 0, "observatii": "str"}, "response": {"id": "str"}},
     "GET /orders/{id}": {"response": {"id": "str", "status": "str", "lines": []}},
+    "PUT /orders/{id}": {"body": {"vehicle_id": "str", "client_id": "str", "tip_deviz_id": "str", "km_intrare": 0, "observatii": "str"}, "note": "Edit header - doar in DRAFT"},
+    "DELETE /orders/{id}": {"response": {"ok": true}, "note": "Stergere - orice nefacturat; FACTURAT = sterge factura intai"},
     "POST /orders/{id}/lines": {"body": {"tip": "manopera|material", "descriere": "str", "ore": 0, "pret_ora": 0, "cantitate": 0, "pret_unitar": 0, "um": "str"}},
     "POST /orders/{id}/validate": {"response": {"status": "VALIDAT"}},
+    "POST /orders/{id}/devalidate": {"response": {"status": "DRAFT"}, "note": "VALIDAT → DRAFT"},
     "GET /orders/{id}/pdf/deviz": {"response": "application/pdf"}
   },
+  "clients": {
+    "GET /clients": {"response": [{"id": "str", "tip_persoana": "PF|PJ", "denumire": "str", "cod_fiscal": "str", "telefon": "str", "email": "str", "activ": true}]},
+    "POST /clients": {"body": {"tip_persoana": "PF|PJ", "denumire": "str", "cod_fiscal": "str", "reg_com": "str", "adresa": "str", "judet": "str", "oras": "str", "cod_postal": "str", "tara": "str", "telefon": "str", "email": "str", "cont_iban": "str", "banca": "str", "observatii": "str"}, "response": {"id": "str"}},
+    "GET /clients/{id}": {"response": {"id": "str", "tip_persoana": "str", "denumire": "str", "cod_fiscal": "str", "vehicles": []}},
+    "PUT /clients/{id}": {"body": {"denumire": "str", "cod_fiscal": "str", "adresa": "str"}, "response": {"id": "str"}},
+    "DELETE /clients/{id}": {"response": {"ok": true}}
+  },
   "vehicles": {
     "GET /vehicles": {"response": [{"id": "str", "nr_auto": "str", "marca": "str", "model": "str", "an": 0}]},
     "POST /vehicles": {"body": {"nr_auto": "str", "marca_id": "str", "model_id": "str", "an_fabricatie": 0, "vin": "str", "proprietar_nume": "str", "proprietar_telefon": "str"}},
@@ -60,8 +70,9 @@
     "POST /p/{token}/reject": {"response": {"ok": true}}
   },
   "invoices": {
-    "POST /invoices": {"body": {"order_id": "str"}, "response": {"id": "str", "nr_factura": "str"}},
-    "GET /invoices/{id}/pdf": {"response": "application/pdf"}
+    "POST /invoices": {"body": {"order_id": "str", "client_id": "str", "tip_document": "FACTURA|BON_FISCAL"}, "response": {"id": "str", "nr_factura": "str"}},
+    "GET /invoices/{id}/pdf": {"response": "application/pdf"},
+    "DELETE /invoices/{id}": {"response": {"ok": true}, "note": "Sterge factura, comanda revine la VALIDAT"}
   },
   "users": {
     "GET /users": {"response": [{"id": "str", "email": "str", "rol": "str"}]},