fix(upload): remove space in filename format and unused UploadResponse struct

src/api/upload.rs

@@ -13,13 +13,6 @@ use crate::auth::session::parse_session_token;
 const ALLOWED_MIME_TYPES: &[&str] = &["image/jpeg", "image/png", "image/gif", "image/webp"];
 const MAX_FILE_SIZE: usize = 5 * 1024 * 1024; // 5MB
 
-#[derive(Debug, Clone, serde::Serialize)]
-struct UploadResponse {
-    success: bool,
-    url: Option<String>,
-    error: Option<String>,
-}
-
 #[cfg(feature = "server")]
 pub async fn upload_image(
     headers: HeaderMap,