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/main.py

@@ -0,0 +1,91 @@
+from contextlib import asynccontextmanager
+from datetime import datetime
+from fastapi import FastAPI
+from fastapi.staticfiles import StaticFiles
+from pathlib import Path
+import logging
+import os
+
+from .config import settings
+from .database import init_oracle, close_oracle, init_sqlite
+
+# Configure logging with both stream and file handlers
+_log_level = getattr(logging, settings.LOG_LEVEL.upper(), logging.INFO)
+_log_format = '%(asctime)s | %(levelname)s | %(name)s | %(message)s'
+_formatter = logging.Formatter(_log_format)
+
+_stream_handler = logging.StreamHandler()
+_stream_handler.setFormatter(_formatter)
+
+_log_dir = os.path.join(os.path.dirname(os.path.dirname(os.path.dirname(__file__))), 'logs')
+os.makedirs(_log_dir, exist_ok=True)
+_log_filename = f"sync_comenzi_{datetime.now().strftime('%Y%m%d_%H%M%S')}.log"
+_file_handler = logging.FileHandler(os.path.join(_log_dir, _log_filename), encoding='utf-8')
+_file_handler.setFormatter(_formatter)
+
+_root_logger = logging.getLogger()
+_root_logger.setLevel(_log_level)
+_root_logger.addHandler(_stream_handler)
+_root_logger.addHandler(_file_handler)
+
+logger = logging.getLogger(__name__)
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    """Startup and shutdown events."""
+    logger.info("Starting GoMag Import Manager...")
+
+    # Initialize Oracle pool
+    try:
+        init_oracle()
+    except Exception as e:
+        logger.error(f"Oracle init failed: {e}")
+        # Allow app to start even without Oracle for development
+
+    # Initialize SQLite
+    init_sqlite()
+
+    # Initialize scheduler (restore saved config)
+    from .services import scheduler_service, sqlite_service
+    scheduler_service.init_scheduler()
+    try:
+        config = await sqlite_service.get_scheduler_config()
+        if config.get("enabled") == "True":
+            interval = int(config.get("interval_minutes", "5"))
+            scheduler_service.start_scheduler(interval)
+    except Exception:
+        pass
+
+    logger.info("GoMag Import Manager started")
+    yield
+
+    # Shutdown
+    scheduler_service.shutdown_scheduler()
+    close_oracle()
+    logger.info("GoMag Import Manager stopped")
+
+app = FastAPI(
+    title="GoMag Import Manager",
+    description="Import comenzi web GoMag → ROA Oracle",
+    version="1.0.0",
+    lifespan=lifespan
+)
+
+# Static files and templates
+static_dir = Path(__file__).parent / "static"
+templates_dir = Path(__file__).parent / "templates"
+static_dir.mkdir(parents=True, exist_ok=True)
+(static_dir / "css").mkdir(exist_ok=True)
+(static_dir / "js").mkdir(exist_ok=True)
+templates_dir.mkdir(parents=True, exist_ok=True)
+
+app.mount("/static", StaticFiles(directory=str(static_dir)), name="static")
+
+# Include routers
+from .routers import health, dashboard, mappings, articles, validation, sync
+app.include_router(health.router)
+app.include_router(dashboard.router)
+app.include_router(mappings.router)
+app.include_router(articles.router)
+app.include_router(validation.router)
+app.include_router(sync.router)