feat(backend): sync endpoints + all models + seed + order workflow

- All business models: Vehicle, Order, OrderLine, Invoice, Appointment,
  CatalogMarca/Model/Ansamblu/Norma/Pret/TipDeviz/TipMotor, Mecanic
- Sync endpoints: GET /sync/full, GET /sync/changes?since=, POST /sync/push
  with tenant isolation and last-write-wins conflict resolution
- Order CRUD with state machine: DRAFT -> VALIDAT -> FACTURAT
  Auto-recalculates totals (manopera + materiale)
- Vehicle CRUD: list, create, get, update
- Seed data: 24 marci, 11 ansamble, 6 tipuri deviz, 5 tipuri motoare, 3 preturi
- Alembic migration for all business models
- 13 passing tests (auth + sync + orders)

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

backend/app/db/seed.py

@@ -0,0 +1,119 @@
+from datetime import UTC, datetime
+
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from app.db.base import uuid7
+from app.db.models.catalog import (
+    CatalogAnsamblu,
+    CatalogMarca,
+    CatalogPret,
+    CatalogTipDeviz,
+    CatalogTipMotor,
+)
+
+MARCI = [
+    "Audi",
+    "BMW",
+    "Citroen",
+    "Dacia",
+    "Fiat",
+    "Ford",
+    "Honda",
+    "Hyundai",
+    "Kia",
+    "Mazda",
+    "Mercedes-Benz",
+    "Mitsubishi",
+    "Nissan",
+    "Opel",
+    "Peugeot",
+    "Renault",
+    "Seat",
+    "Skoda",
+    "Suzuki",
+    "Toyota",
+    "Volkswagen",
+    "Volvo",
+    "Alfa Romeo",
+    "Jeep",
+]
+
+ANSAMBLE = [
+    "Motor",
+    "Cutie de viteze",
+    "Frane",
+    "Directie",
+    "Suspensie",
+    "Climatizare",
+    "Electrica",
+    "Caroserie",
+    "Esapament",
+    "Transmisie",
+    "Revizie",
+]
+
+TIPURI_DEVIZ = [
+    "Deviz reparatie",
+    "Deviz revizie",
+    "Deviz diagnosticare",
+    "Deviz estimativ",
+    "Deviz vulcanizare",
+    "Deviz ITP",
+]
+
+TIPURI_MOTOARE = ["Benzina", "Diesel", "Hibrid", "Electric", "GPL"]
+
+PRETURI = [
+    {"denumire": "Manopera standard", "pret": 150.0, "um": "ora"},
+    {"denumire": "Revizie ulei + filtru", "pret": 250.0, "um": "buc"},
+    {"denumire": "Diagnosticare", "pret": 100.0, "um": "buc"},
+]
+
+
+async def seed_catalog(db: AsyncSession, tenant_id: str) -> dict:
+    now = datetime.now(UTC).isoformat()
+    counts = {}
+
+    # Marci
+    for name in MARCI:
+        db.add(
+            CatalogMarca(id=uuid7(), tenant_id=tenant_id, nume=name)
+        )
+    counts["marci"] = len(MARCI)
+
+    # Ansamble
+    for name in ANSAMBLE:
+        db.add(
+            CatalogAnsamblu(id=uuid7(), tenant_id=tenant_id, nume=name)
+        )
+    counts["ansamble"] = len(ANSAMBLE)
+
+    # Tipuri deviz
+    for name in TIPURI_DEVIZ:
+        db.add(
+            CatalogTipDeviz(id=uuid7(), tenant_id=tenant_id, nume=name)
+        )
+    counts["tipuri_deviz"] = len(TIPURI_DEVIZ)
+
+    # Tipuri motoare
+    for name in TIPURI_MOTOARE:
+        db.add(
+            CatalogTipMotor(id=uuid7(), tenant_id=tenant_id, nume=name)
+        )
+    counts["tipuri_motoare"] = len(TIPURI_MOTOARE)
+
+    # Preturi
+    for p in PRETURI:
+        db.add(
+            CatalogPret(
+                id=uuid7(),
+                tenant_id=tenant_id,
+                denumire=p["denumire"],
+                pret=p["pret"],
+                um=p["um"],
+            )
+        )
+    counts["preturi"] = len(PRETURI)
+
+    await db.commit()
+    return counts