🎨 fix(web): align UI and charts with theme tokens and presets

Improve theme switching fidelity (including system preference), extend design tokens so color presets tint real surfaces—not only primary/chrome—and refactor shared badges, tables, and dashboard visuals to semantic colors. Wire VChart series colors to `--chart-*` with safe fallbacks.

**Changes**

- **Theme runtime** (`theme-provider.tsx`): Validate stored theme cookie; keep `resolvedTheme` in sync with DOM + `(prefers-color-scheme)`; `resetTheme` respects `defaultTheme`; memoized context value.
- **Tokens** (`theme.css`): Add `--success|warning|info|neutral` (+ foregrounds) and map them under `@theme inline` for Tailwind utilities.
- **Presets** (`theme-presets.css`): For non-`default` presets, derive `card`, `popover`, `muted`, `accent`, `border`, `input`, and sidebar tokens from `--primary`/`--background`; map semantic status colors to preset chart variables.
- **Components**: `status-badge`, `colors` (avatars, announcements), `copy-button`, `group-badge`, `data-table` row styles, `sidebar` outline shadow (fix `var(--sidebar-border)` usage), ai-elements tool/web-preview status colors.
- **Dashboard**: Latency/API helpers and overview fragments use semantic tokens; `charts.ts` reads `--chart-1`…`--chart-5` from computed styles with fallbacks; `processChartData` / `processUserChartData` accept optional `themeKey` for preset churn; chart components pass `customization.preset` and bump `VChart` keys.

**Verification**

- `bun run typecheck`

web/default/src/components/copy-button.tsx

@@ -50,7 +50,7 @@ export function CopyButton({
       aria-label={isCopied ? copiedAriaLabel : resolvedAriaLabel}
     >
       {isCopied ? (
-        <Check className={cn('text-green-600', iconClassName)} />
+        <Check className={cn('text-success', iconClassName)} />
       ) : (
         <Copy className={cn(iconClassName)} />
       )}