fix(ci): separate format check from lint check

- Change format:check to use `biome format .` instead of `biome check .`
- biome check runs both formatting AND linting (causing failures on warnings)
- biome format only checks formatting (linting is handled by separate lint job)
- This prevents a11y warnings from failing the format check

Fixes format-check CI failures.

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

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

package.json

@@ -15,7 +15,7 @@
     "test:ui": "turbo test:ui",
     "lint": "turbo lint",
     "format": "biome format --write .",
-    "format:check": "biome check .",
+    "format:check": "biome format .",
     "type-check": "turbo type-check",
     "type-coverage": "type-coverage --at-least 95",
     "find-deadcode": "knip",