Update CONTRIBUTING.md to enhance clarity on testing themes with test-site.html [skip ci]

CONTRIBUTING.md

@@ -270,9 +270,9 @@ You can test your theme without a Jellyfin server by using the included test sit
 ### Steps
 
 1. Navigate to the `Jellyfin.Plugin.Seasonals/Web/` directory
-2. Open `test-site.html` in your browser (just double-click the file) or vscode or what ever you use...
+2. Open [`test-site.html`](./Jellyfin.Plugin.Seasonals/Web/test-site.html) in your browser (just double-click the file) or vscode or what ever you use...
 3. Use the **theme selector dropdown** to pick an existing theme or select **"Custom (Local Files)"** to test your own
-4. When "Custom" is selected, enter your theme's JS and CSS filenames (e.g., `mytheme.js` and `mytheme.css` (must be in the same folder as `test-site.html` for this to work))
+4. When "Custom" is selected, enter your theme's JS and CSS filenames (e.g., `mytheme.js` and `mytheme.css` (must be in the same folder as [`test-site.html`](./Jellyfin.Plugin.Seasonals/Web/test-site.html) for this to work))
 5. Click **"Load Theme"** to apply. Click **"Clear & Reload"** to reset and try again
 
 ### What to Verify
@@ -293,7 +293,7 @@ You can test your theme without a Jellyfin server by using the included test sit
 - [ ] Created `{themeName}.css` following the [CSS pattern](#css-file-pattern)
 - [ ] (If applicable) Created `{themeName}_images/` with optimized assets
 - [ ] Added theme to `ThemeConfigs` in `seasonals.js`
-- [ ] Tested locally with `test-site.html`
+- [ ] Tested locally with [`test-site.html`](./Jellyfin.Plugin.Seasonals/Web/test-site.html)
 - [ ] No theme related console errors
 - [ ] Effect has `pointer-events: none` (doesn't block the UI)
 - [ ] Effect hides during video/trailer playback (toggle function implemented)