feat: modernize Tooltip to the latest Material Design specs

The goal is to modernize the Tooltip according to the latest specs - see below.

# Current State

## Tooltip

**MD3 spec:** Tooltips
**Specs link:** https://m3.material.io/components/tooltips/specs

### Color tokens

- [ ] Container background uses `theme.colors.onSurface`; spec requires `inverseSurface`
- [ ] Text color uses `theme.colors.surface`; spec requires `inverseOnSurface`

### Shape

- `borderRadius: theme.roundness` = 4dp matches `corner.extraSmall` ✅

### Spacing / sizing

- Container height 32dp ✅
- [ ] Text variant is `labelLarge` (14sp); spec requires `bodySmall` (12sp)

### Behavior

- [ ] Rich tooltip variant not implemented. MD3 defines two variants: plain (text only) and rich (optional title, body text, link, and action buttons). The current `title: string` prop cannot support rich content
- No pointer/caret indicator (not required by spec) ✅

### Animation

- [ ] No enter/exit animation. MD3 specifies a fade transition on show/hide

从现有的 Tooltip 实现开始，将其当前行为与链接的 Material Design 3 Tooltip 规范进行比较。检查清单，包括颜色 token、文本大小、富内容支持和淡入淡出过渡；现有的 title prop 被特别指出。完成意味着实现列出的未勾选要求，同时保持已经匹配的行为不变。

由索引模型根据 Issue 内容生成。