feat: add alt text extraction from URLs for images and improve CSS variable usage for progress bars

Add `_alt_from_url` helper in Python rendering and `altFromUrl` in JS ContentRenderer to generate descriptive alt attributes from image filenames, replacing empty alt strings. Update image embed templates and Avatar component to use derived alt text. Migrate inline `style.width` assignments to CSS custom properties (`--poll-pct`, `--hud-xp`, `--quest-pct`, `--bar-pct`, `--quota-pct`) across PollManager, GameFarm, and profile/quest CSS for better maintainability. Introduce new admin, docs, projects, services, and base CSS utility classes. Add "Code Farm" docs page entry.

devplacepy/templates/_comment_form.html

@@ -13,7 +13,7 @@
     </div>
 </form>
 {% else %}
-<form class="comment-form comment-form-guest" onsubmit="return false">
+<form class="comment-form comment-form-guest">
     <textarea name="content" placeholder="Your opinion goes here..." disabled aria-disabled="true" aria-label="Comment"></textarea>
     <div class="comment-form-actions">
         <button type="button" class="comment-form-submit" disabled aria-disabled="true"><span class="icon">&#x1F4E4;</span><span class="label"> Post</span></button>