fix: correct public file path handling in get_public_file function

- Moved the public_path assignment to ensure it is set before checking for the file's existence.
- This change resolves potential issues when accessing files in the public directory.

app.py

@@ -197,12 +197,12 @@ def generate_sitemap():
 # Mount all files from public directory to root
 @app.get("/{filename}")
 async def get_public_file(filename: str):
-    public_path = os.path.join("public", filename)
     if filename == "sitemap.xml":
         return Response(
         content=generate_sitemap(),
         media_type="application/xml"
     )
+    public_path = os.path.join("public", filename)
     if os.path.isfile(public_path):
         return FileResponse(public_path)
     raise HTTPException(status_code=404, detail="File not found")