ci: add whiskers check

Author: sgoudham

.github/workflows/check.yml

@@ -0,0 +1,19 @@
+name: Whiskers Check
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: catppuccin/setup-whiskers@v1
+        with:
+          whiskers-version: 2.5.1
+      - run: |
+          whiskers templates/editor.tera --check
+          whiskers templates/ui.tera --check ui-theme.md