feat: align chat rendering with CLI and trim frontend load weight

- Merge thinking and assistant text into one assistant bubble with ordered blocks

- Restyle tool execution blocks to match CLI layout and status

- Remove startup splash screen and ship woff2-only fonts in public

- Add default avatars when agent or user image is unset

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/.gitignore

@@ -1,3 +1,4 @@
 node_modules
 dist/
-dist-desketop/
+dist-desketop/
+public/fonts/*.ttf