ui: Update KaTeX package and clean up logs from sass warnings (ggml-org#23275)

* ui: migrate katex imports to @use to resolve SCSS deprecation warnings

* ci: Use `ubuntu-slim` for CI (UI) workflow

Author: allozaur

.github/workflows/ui-ci.yml

@@ -41,7 +41,7 @@ jobs:
   ui-checks:
     name: UI Checks
     needs: ui-build
-    runs-on: ubuntu-24.04-arm
+    runs-on: ubuntu-slim
     continue-on-error: true
     steps:
       - name: Checkout code
@@ -93,7 +93,7 @@ jobs:
   e2e-tests:
     name: E2E Tests
     needs: ui-build
-    runs-on: ubuntu-24.04-arm
+    runs-on: ubuntu-slim
     steps:
       - name: Checkout code
         uses: actions/checkout@v6

tools/ui/package-lock.json

@@ -8,6 +8,9 @@ $use-ttf: false;
 $font-folder: 'katex-fonts';
 
 // Import KaTeX SCSS with overridden variables
-// Note: @import is deprecated but required because KaTeX uses @import internally
-// The deprecation warnings are from KaTeX's code and cannot be avoided
-@import 'katex/src/styles/katex.scss';
+@use 'katex/src/styles/katex.scss' with (
+	$use-woff2: true,
+	$use-woff: false,
+	$use-ttf: false,
+	$font-folder: 'katex-fonts'
+);

tools/ui/src/styles/katex-custom.scss

@@ -23,18 +23,6 @@ export default defineConfig({
 		minify: true
 	},
 
-	css: {
-		preprocessorOptions: {
-			scss: {
-				additionalData: `
-					$use-woff2: true;
-					$use-woff: false;
-					$use-ttf: false;
-				`
-			}
-		}
-	},
-
 	plugins: [tailwindcss(), sveltekit(), devtoolsJson(), llamaCppBuildPlugin()],
 
 	test: {