feat: add common view module

gallery/easel/route/view/common/__init__.py

@@ -0,0 +1,9 @@
+from pathlib import Path
+
+from fastapi import FastAPI
+from fastapi.staticfiles import StaticFiles
+
+
+def mount(app: FastAPI):
+    base_dir = Path(__file__).parent
+    app.mount("/static/common", StaticFiles(directory=base_dir / "static"))