0.8.3: custom tooltips, editor-hide, pack script, settings reshuffle

Tooltips
- New v-tooltip directive + TooltipHost floating panel replace the
  native title attribute across 95+ sites (topbar, timeline, sidebar,
  properties, stage overlays, fullscreen preview, export dialog,
  clipart drawer, modals). Styled dark card with a configurable
  label + optional help line for inline documentation; screen
  readers still get an aria-label when the panel is disabled.
- Settings → Interface toggle (`ruwio:tooltipsEnabled`) hides the
  visual panel for users who know the app. IconButton now routes
  its title prop through v-tooltip so every existing call site is
  tooltip-aware without churn.

Editor-hide + export filter
- New `Layer.editorHidden` flag, eye toggle per layer row, skipped
  by the Konva stage and the mask-preview canvas path but honoured
  by exports and fullscreen preview (runtime untouched).
- Export dialog gets a "Skip hidden tracks" switch that strips
  editor-hidden layers from every format (scene JS, runtime,
  example HTML, MP4, WebM) on opt-in. Disabled when the scene has
  no hidden layers.

Button editor
- `+` buttons appear on empty state slots in button-timeline rows
  and duplicate the nearest keyframe (prev by preference, next
  otherwise) onto that slot. New `duplicateKeyframeAt` store
  action carries props, easing, hold, and bezier handles across.

Stage / interaction
- Plain left-click on the empty content view pans the viewport,
  but only when the pointer isn't over a Konva shape — transformer
  handles, vertex dots, and selection boxes that extend past the
  canvas edge keep their drag.

Settings reshuffle
- Timeline tab merged into Document (Duration + FPS sit under a
  new "Timing" sub-heading). New Interface tab gathers three
  global prefs: Show tooltips, Show locked tracks, Asset
  thumbnails — driven by shared composables so the existing
  toolbar toggles stay in sync. Interface-tab CSS defensively
  resets the scoped label flex-column + uppercase rule that was
  making the toggle row look like an accident.

Project identity + UX polish
- Favicon wired up (moved to public/favicon.ico, linked from
  index.html); scripts/pack.sh packs the minimum Vue project
  (src, index.html, configs, public) into a tarball with the
  right version in the filename, and `npm run pack` drives it.
- About dialog now credits Torsten Hoeltge.

Test infra
- Progress bar turns red mid-run on the first failure: runAll
  gets an onResult callback that TestOverlay uses to push each
  result into the reactive array incrementally.
- mountComponent in the test harness registers v-tooltip on the
  isolated app instance so IconButton's aria-label contract
  actually fires under test.

Regression tests
- duplicateKeyframeAt: copy fidelity (props, easing, hold),
  collision refusal, unknown-id guards, separated-track targeting.
- Shared composables: useTooltipPref and useAssetThumbsPref both
  return the same ref across calls and persist to localStorage.
- Tooltip contract: IconButton ships `aria-label` (not title);
  live-DOM smoke tests match on aria-label selectors now.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/lib/render.ts

@@ -136,6 +136,12 @@ function drawLayers(
   for (let i = layers.length - 1; i >= 0; i--) {
     const layer = layers[i]
     if (!layer.visible) continue
+    // Editor-only hide: respected by the mask-preview overlay and
+    // sidebar thumbnails so toggling a layer off really removes it
+    // from the in-editor render. The runtime in exportPlayer.ts does
+    // NOT read this flag, so fullscreen preview and exports keep
+    // rendering the layer.
+    if (layer.editorHidden) continue
     if (!alwaysActive && !isLayerActiveAt(layer, time)) continue
     const asset = assetMap.get(layer.assetId)
     if (!asset) continue