Loading skeletons and Suspense boundaries

[satsdisco]

Summary

Currently the app shows either nothing or a loading spinner while content fetches from relays. Skeleton screens provide a much better perceived performance and feel more polished.

Where needed

• Press page — article card skeletons while fetching from relays
• Article reader — content skeleton while loading article + profile
• Editor — loading state while restoring draft
• Login — connection status while authenticating with bunker/extension
• Route transitions — Suspense fallback for lazy-loaded routes (see Add route-level code splitting with React.lazy() #9)

Design

• Match the warm Samizdat aesthetic (paper/cream tones)
• Subtle pulse animation, not harsh grey blocks
• Show structure: title bar, paragraph lines, author avatar placeholder

Acceptance Criteria

• No blank/white screens during loading
• Skeletons match final layout structure
• Smooth transition from skeleton → real content
• Works on slow relay connections (3G simulation)