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/project_detail.html

@@ -43,7 +43,7 @@
             {% set _size = 32 %}{% set _size_class = "sm" %}{% set _user = author %}{% include "_avatar_link.html" %}
             <div>
                 {% set _user = author %}{% set _class = none %}{% include "_user_link.html" %}
-                <span style="font-size: 0.75rem; color: var(--text-muted);">&middot; Level {{ author.get('level', 1) if author else 1 }}</span>
+                <span class="meta-muted">&middot; Level {{ author.get('level', 1) if author else 1 }}</span>
             </div>
         </div>
 
@@ -54,8 +54,8 @@
         {% endif %}
 
         {% if platforms %}
-        <div style="margin-bottom: 1.5rem;">
-            <h4 style="font-size: 0.75rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.1em; color: var(--text-muted); margin-bottom: 0.5rem;">Platforms</h4>
+        <div class="project-platforms">
+            <h4 class="project-section-label">Platforms</h4>
             <div class="project-card-platforms">
                 {% for plat in platforms %}
                 <span class="platform-tag">{{ plat.strip() }}</span>