- Add .has-tooltip CSS utility class with 300ms delay (vs ~1500ms native)
- Position-aware: right side for rail buttons, bottom for nav/panel buttons
- Arrow indicator pointing back at trigger element
- :focus-visible support for keyboard accessibility
- prefers-reduced-motion: no animation for users who opt out
- Replace native title="" with data-tooltip="" on all rail-btn, sidebar
nav-tab, and panel-head-btn elements in index.html
- Sync data-tooltip via data-i18n-title handler for locale switching
- 17 tests covering HTML coverage, CSS class definitions, and i18n sync
Closes#1775
b86bdf9dc8
