feat(workspace): sliding sidebar in focus mode, calmer workspace bar, smoother journal

- focus mode: folders slide in from the left (button, title click, or the
  left edge on wide screens); picking a note keeps focus mode
- workspace bar: borderless live/shared/save pills in one style, divider
  before the note actions; footer without top line
- journal panel and calendar open with an animation, the view fades in
- paste and markdown import nest a list under the paragraph introducing it

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/src/components/AppFooter.tsx

@@ -10,7 +10,7 @@ interface AppFooterProps {
 
 export const AppFooter: React.FC<AppFooterProps> = ({ legal, onOpenAbout }) => {
   return (
-    <footer className="hidden sm:flex shrink-0 w-full max-w-6xl mx-auto px-4 py-2 items-center justify-between text-[11px] text-faint border-t border-border/40 select-none">
+    <footer className="hidden sm:flex shrink-0 w-full max-w-6xl mx-auto px-4 py-2 items-center justify-between text-[11px] text-faint select-none">
       <div className="flex items-center gap-3">
         <button
           type="button"