feat: add FastAPI admin dashboard with sync orchestration and test suite

Replace Flask admin with FastAPI app (api/app/) featuring:
- Dashboard with stat cards, sync control, and history
- Mappings CRUD for ARTICOLE_TERTI with CSV import/export
- Article autocomplete from NOM_ARTICOLE
- SKU pre-validation before import
- Sync orchestration: read JSONs -> validate -> import -> log to SQLite
- APScheduler for periodic sync from UI
- File logging to logs/sync_comenzi_YYYYMMDD_HHMMSS.log
- Oracle pool None guard (503 vs 500 on unavailable)

Test suite:
- test_app_basic.py: 30 tests (imports + routes) without Oracle
- test_integration.py: 9 integration tests with Oracle

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

api/app/routers/sync.py

@@ -0,0 +1,90 @@
+from fastapi import APIRouter, Request, BackgroundTasks
+from fastapi.templating import Jinja2Templates
+from fastapi.responses import HTMLResponse
+from pydantic import BaseModel
+from pathlib import Path
+from typing import Optional
+
+from ..services import sync_service, scheduler_service, sqlite_service
+
+router = APIRouter(tags=["sync"])
+templates = Jinja2Templates(directory=str(Path(__file__).parent.parent / "templates"))
+
+
+class ScheduleConfig(BaseModel):
+    enabled: bool
+    interval_minutes: int = 5
+
+
+# HTML pages
+@router.get("/sync", response_class=HTMLResponse)
+async def sync_page(request: Request):
+    return templates.TemplateResponse("dashboard.html", {"request": request})
+
+
+@router.get("/sync/run/{run_id}", response_class=HTMLResponse)
+async def sync_detail_page(request: Request, run_id: str):
+    return templates.TemplateResponse("sync_detail.html", {"request": request, "run_id": run_id})
+
+
+# API endpoints
+@router.post("/api/sync/start")
+async def start_sync(background_tasks: BackgroundTasks):
+    """Trigger a sync run in the background."""
+    status = await sync_service.get_sync_status()
+    if status.get("status") == "running":
+        return {"error": "Sync already running", "run_id": status.get("run_id")}
+
+    background_tasks.add_task(sync_service.run_sync)
+    return {"message": "Sync started"}
+
+
+@router.post("/api/sync/stop")
+async def stop_sync():
+    """Stop a running sync."""
+    sync_service.stop_sync()
+    return {"message": "Stop signal sent"}
+
+
+@router.get("/api/sync/status")
+async def sync_status():
+    """Get current sync status."""
+    status = await sync_service.get_sync_status()
+    stats = await sqlite_service.get_dashboard_stats()
+    return {**status, "stats": stats}
+
+
+@router.get("/api/sync/history")
+async def sync_history(page: int = 1, per_page: int = 20):
+    """Get sync run history."""
+    return await sqlite_service.get_sync_runs(page, per_page)
+
+
+@router.get("/api/sync/run/{run_id}")
+async def sync_run_detail(run_id: str):
+    """Get details for a specific sync run."""
+    detail = await sqlite_service.get_sync_run_detail(run_id)
+    if not detail:
+        return {"error": "Run not found"}
+    return detail
+
+
+@router.put("/api/sync/schedule")
+async def update_schedule(config: ScheduleConfig):
+    """Update scheduler configuration."""
+    if config.enabled:
+        scheduler_service.start_scheduler(config.interval_minutes)
+    else:
+        scheduler_service.stop_scheduler()
+
+    # Persist config
+    await sqlite_service.set_scheduler_config("enabled", str(config.enabled))
+    await sqlite_service.set_scheduler_config("interval_minutes", str(config.interval_minutes))
+
+    return scheduler_service.get_scheduler_status()
+
+
+@router.get("/api/sync/schedule")
+async def get_schedule():
+    """Get current scheduler status."""
+    return scheduler_service.get_scheduler_status()