Add sync module: push seed data to main app DB (dev/prod)

- New sync.py: reads seed import's 39-col schema, maps to main app's
  customers/locations/assets schema with foreign keys
- New POST /api/sync endpoint (target=dev|prod, dry_run=true/false)
- New GET /api/sync/targets endpoint
- Category mapping: Bev→Beverage, Snack→Snack, Food→Food, etc.
- Automatically creates customers and locations from company/place
- Idempotent: updates existing assets by machine_id
- Dry-run mode: preview changes without writing

web/server.py

@@ -37,6 +37,7 @@ sys.path.insert(0, str(PROJECT_ROOT))
 from parser import parse_excel
 from db_writer import write_seed, write_update, ALL_COLUMNS, PRESERVE_FIELDS, AUTO_FIELDS
 from backup import backup as do_backup, compare as compare_backup
+from sync import push as sync_push, TARGETS as SYNC_TARGETS
 
 
 # ─── Helpers ──────────────────────────────────────────────────────────────────
@@ -550,6 +551,43 @@ async def api_db_wipe(db_path: str = Query(DEFAULT_DB_PATH)):
         raise HTTPException(500, f"Wipe error: {e}")
 
 
+# ─── Sync / Push to Main App ──────────────────────────────────────────────────
+
+
+@app.post("/api/sync")
+async def api_sync(
+    target: str = Query("dev"),
+    dry_run: bool = Query(False),
+):
+    """Push seed import data to the main app database."""
+    if target not in SYNC_TARGETS:
+        raise HTTPException(400, f"Unknown target: {target}. Options: {list(SYNC_TARGETS.keys())}")
+    target_db = SYNC_TARGETS[target]["path"]
+    source_db = DEFAULT_DB_PATH
+    report = sync_push(source_db, target_db, dry_run=dry_run)
+    if "error" in report:
+        raise HTTPException(500, report["error"])
+    return report
+
+
+@app.get("/api/sync/targets")
+async def api_sync_targets():
+    """Return available sync targets."""
+    return {
+        "targets": {
+            name: {
+                "path": info["path"],
+                "exists": os.path.exists(info["path"]),
+            }
+            for name, info in SYNC_TARGETS.items()
+        },
+        "source": {
+            "path": DEFAULT_DB_PATH,
+            "exists": os.path.exists(DEFAULT_DB_PATH),
+        },
+    }
+
+
 # ─── Static files ─────────────────────────────────────────────────────────────
 
 STATIC_DIR = Path(__file__).parent / "static"