Add save timestamp support and log interceptor for enhanced debugging

- Introduced `created_at` metadata for saves, enabling timestamp tracking.
- Added `InterceptorLogger` to capture logs, aiding in error diagnostics.
- Updated web UI to display save creation timestamps.
- Improved save/load functionality to maintain compatibility with older formats.

Software/MainBoard/rust/src_webpack/src/api.ts

@@ -37,6 +37,7 @@ export interface NetworkConfig {
 export interface SaveInfo {
     idx: number,
     len: number,
+    created_at: string | null,
 }
 
 export interface FileList {