Add TanStack Query and update dashboard card styling

- Set up @tanstack/svelte-query and devtools in root layout
- Configure QueryClient with 5-minute stale time
- Update dashboard card to match Figma: regular font weight, no border
- Add .playwright-mcp to gitignore

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.gitignore

@@ -42,3 +42,6 @@ yarn-error.log*
 # Misc
 *.pem
 .vercel
+
+.playwright-mcp/
+