Backport: Css token standardization (#6363) (#6669)

## Summary
Backports the CSS token standardization changes from PR #6363 to the
`core/1.30` branch.

Resolved merge conflict in `MediaTitle.vue` and added missing
`truncateFilename` function to maintain compatibility.

**Original PR**: https://github.com/Comfy-Org/ComfyUI_frontend/pull/6363
**Cherry-picked commit**: bde5244a71

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-6669-Backport-Css-token-standardization-6363-2aa6d73d36508153be09cdc67f6ac8a4)
by [Unito](https://www.unito.io)

packages/shared-frontend-utils/src/formatUtil.ts

@@ -474,3 +474,13 @@ export function formatDuration(milliseconds: number): string {
 
   return parts.join(' ')
 }
+
+/**
+ * Truncates a filename for display purposes.
+ * Currently returns the filename as-is since truncation is handled by CSS.
+ * @param filename The filename to truncate
+ * @returns The display-ready filename
+ */
+export function truncateFilename(filename: string): string {
+  return filename
+}