Tracking: PieceList UI update

[shaoster]

For Mobile: converge on https://shaoster.github.io/glaze/claude_designs/Piece%20List%20v2.html

Claude Design's key points:

• 2-col masonry via CSS columns — cards have 3 thumbnail heights based on activity (≤2d tall, 3–13d medium, stale/terminal short). Variable heights flow naturally without ragged rows.
• Detail-consistent chip grammar — current state is now a filled terracotta pill (matches Piece Detail A's current-state treatment); terminal states use a quiet glass chip with the kind-color dot. Tags demoted to soft dot+label pills. Combine filter and tag selectors in PieceDetail #208
• Thumbnails enlarged, with overlays: filled state chip bottom-left, photo count top-left, kiln-glow stale dot top-right (≥14d in non-terminal state).
• Last-activity caption in mono: 3d ago · 3d in trimming. Stale duration pulses kiln-red.
• Tags truncated to 2 + dashed +N overflow chip. Tag overflow capability for use in PieceList #203
• Bottom tab bar (Pieces / Analyze) with active state in accent color.
• Condensed filter — single tappable pill that expands to chip filters, with sorting. (Missing piece is PieceList standard sort and pagination #216)
• Strong-shadow FAB — layered inset highlight, inset shadow, double drop-shadow + accent halo for clear elevation against any card.