RESTORE ALL FILES from original working commit + only add .hidden CSS

Add .open CSS rule for vaistudio panel visibility

Add .hidden CSS class for vaistudio loading spinner fix

Restore style.css to commit 14581f08 (draggable/resizable text chat, no text-chat-row/avatar-loading)

Add proper CSS for text chat and avatar loading overlay

Restore src/style.css from victor/gemma-avatar

Upload src/style.css