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/components/PropertiesPanel.vue

@@ -384,7 +384,7 @@ function removeKeyframeHere() {
           {{ hasKeyframeHere ? t('properties.keyframeLabel') : t('properties.interpolated') }}
           <span class="kf-time">@ {{ store.playhead.toFixed(2) }}s</span>
         </span>
-        <button v-if="hasKeyframeHere" class="kf-btn" :title="t('properties.removeKeyframe')" @click="removeKeyframeHere">
+        <button v-if="hasKeyframeHere" class="kf-btn" v-tooltip="t('properties.removeKeyframe')" @click="removeKeyframeHere">
           <PhX :size="12" weight="bold" />
         </button>
       </div>
@@ -430,7 +430,7 @@ function removeKeyframeHere() {
               type="button"
               class="icon-toggle"
               :class="{ active: polygonClosed }"
-              :title="t('properties.polygonClosed')"
+              v-tooltip="t('properties.polygonClosed')"
               @click="polygonClosed = !polygonClosed"
             >
               <PhPolygon :size="14" :weight="polygonClosed ? 'fill' : 'regular'" />
@@ -465,7 +465,7 @@ function removeKeyframeHere() {
                 type="button"
                 class="icon-toggle alpha-toggle-btn"
                 :class="{ active: fillTransparent }"
-                :title="t('properties.transparent')"
+                v-tooltip="t('properties.transparent')"
                 @click="fillTransparent = !fillTransparent"
               >
                 <component :is="fillTransparent ? PhEyeSlash : PhEye" :size="13" />
@@ -487,7 +487,7 @@ function removeKeyframeHere() {
                 type="button"
                 class="icon-toggle alpha-toggle-btn"
                 :class="{ active: strokeTransparent }"
-                :title="t('properties.transparent')"
+                v-tooltip="t('properties.transparent')"
                 @click="strokeTransparent = !strokeTransparent"
               >
                 <component :is="strokeTransparent ? PhEyeSlash : PhEye" :size="13" />
@@ -588,7 +588,7 @@ function removeKeyframeHere() {
               type="button"
               class="icon-toggle"
               :class="{ active: !!selected.isMask }"
-              :title="t('properties.maskUse')"
+              v-tooltip="t('properties.maskUse')"
               @click="store.setLayerMask(selected.id, !selected.isMask)"
             >
               <PhMaskHappy :size="14" />
@@ -601,7 +601,7 @@ function removeKeyframeHere() {
                 type="button"
                 class="icon-toggle"
                 :class="{ active: (selected.maskMode ?? 'negative') === 'negative', danger: (selected.maskMode ?? 'negative') === 'negative' }"
-                :title="t('properties.maskNegative')"
+                v-tooltip="t('properties.maskNegative')"
                 @click="store.setLayerMaskMode(selected.id, 'negative')"
               >
                 <PhMinus :size="13" weight="bold" />
@@ -610,7 +610,7 @@ function removeKeyframeHere() {
                 type="button"
                 class="icon-toggle"
                 :class="{ active: selected.maskMode === 'positive' }"
-                :title="t('properties.maskPositive')"
+                v-tooltip="t('properties.maskPositive')"
                 @click="store.setLayerMaskMode(selected.id, 'positive')"
               >
                 <PhPlus :size="13" weight="bold" />