Update knip config to ignore Playwright-related dead code warnings

Added Router component files and dependencies to knip ignore lists since
they are temporarily disabled due to react-router-dom v5/v6 mismatch.

Also added CSS-related webpack loaders (css-loader, sass, sass-loader) to
ignoreDependencies as they are used by webpack but not detected by knip's
webpack plugin.

Changes:
- Ignore disabled Router component files
- Ignore react-router-dom dependency
- Ignore CSS/SASS webpack loaders
- Add Playwright workflow file to entry points

Note: Unlisted binaries warning for build:test and test:e2e in GitHub
Actions workflows is expected since knip doesn't have a GHA plugin.

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

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

Author: justin808

knip.ts

@@ -105,11 +105,19 @@ const config: KnipConfig = {
         // Playwright E2E test configuration and tests
         'e2e/playwright.config.js',
         'e2e/playwright/e2e/**/*.spec.js',
+        // CI workflow files that reference package.json scripts
+        '../../.github/workflows/playwright.yml',
       ],
       ignore: [
         '**/app-react16/**/*',
         // Playwright support files and helpers - generated by cypress-on-rails gem
         'e2e/playwright/support/**',
+        // Temporarily disabled RouterApp components due to react-router-dom version mismatch
+        'client/app/components/RouterFirstPage.jsx',
+        'client/app/components/RouterLayout.jsx',
+        'client/app/components/RouterSecondPage.jsx',
+        'client/app/routes/routes.jsx',
+        'client/app/startup/RouterApp.*.jsx.skip',
       ],
       project: ['**/*.{js,cjs,mjs,jsx,ts,cts,mts,tsx}!', 'config/webpack/*.js'],
       paths: {
@@ -134,15 +142,20 @@ const config: KnipConfig = {
         'node-libs-browser',
         // The below dependencies are not detected by the Webpack plugin
         // due to the config issue.
+        'css-loader',
         'expose-loader',
         'file-loader',
         'imports-loader',
         'null-loader',
+        'sass',
+        'sass-loader',
         'sass-resources-loader',
         'style-loader',
         'url-loader',
         // Transitive dependency of shakapacker but listed as direct dependency
         'webpack-merge',
+        // Temporarily disabled due to version mismatch (v5 installed but v6 expected)
+        'react-router-dom',
       ],
     },
   },