Add GnRepeater component for dynamic field groups ...

- New Vue adapter: GnRepeater with v-model, scoped #item slot,
  minItems/maxItems guards, and built-in Add/Remove UI
- SCSS: .repeater, .repeater-header, .repeater-item,
  .repeater-item-body, .repeater-item-actions
- Demo: vanilla repeater with inline JS + GnRepeater in Vue forms
- Build verified: compare-heights reports 0 differences

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Add GnTagInput component for multi-value string input ...

Features:
- New GnTagInput Vue component with inline chip display
- Enter / paste (with separator split) to add tags
- Backspace in empty field removes last tag
- Unique check and maxItems limit
- Removable chips with x button

Style:
- Add _tag-input.scss with .tag-input, .tag-input-wrap, .tag-input-field
- Chips reuse existing .chip-secondary styling

Demo:
- Add interactive tag input example to Forms section (vanilla + Vue)
- Add code example blocks for HTML and Vue usage

Docs:
- Add GnTagInput to CLAUDE.md component catalog

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

v0.3.0 — GnUserCard, NavigationShell footer slot, Vue demo partials ...

Features:
- Add GnUserCard Vue component with compact and full variants
- Add GnNavigationShell #footer slot for custom footer content
- Add profile footer demo in navigation-shell section
- Split demo/vue.html into 27 partials under demo/partials/vue/
- Fix toast open animation (nextTick + requestAnimationFrame pattern)

Style:
- Add .user-card and .user-card-compact to _cards.scss
- Add .profile-identity to _navigation-shell.scss

Docs:
- Add demo synchronization rules to CLAUDE.md

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>