A simpler, review-first main viewer built in Vue, routed through the
existing OPEN_VIEWER event so every caller keeps working:
- Header with navigation, file summary and actions; zoom/pan image
stage (cursor-anchored wheel zoom, fit/1:1, transparency checker).
- New video/audio player: frame stepping and counter, A-B loop, loop,
speed, volume, fullscreen, save frame as PNG, auto-hiding controls;
media is released on change/close.
- Inspector reusing the asset sidebar's rating, tags, generation,
workflow and file components, hydrated with the viewer metadata
cache; filmstrip windowed for large lists; keyboard shortcuts.
- The classic viewer stays for A/B and side-by-side compare, 3D models
and its analysis tools, and as an opt-in setting.