fix: Correct version selector to show current version as selected

Fix version selector dropdown to properly select the currently displayed
version by comparing version objects instead of comparing version name
with current_version string.

Changed comparison from `item.name == current_version` to
`item == current_version` to properly match the current version object.

Now:
- v3.12.2 page shows v3.12.2 as selected
- master page shows master as selected

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

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

Author: laughingman7743

docs/_templates/versioning.html

@@ -4,8 +4,8 @@
   <div class="version-dropdown" style="margin-bottom: 1rem;">
     <select onchange="window.location.href = this.value" style="width: 100%; padding: 0.5rem; border: 1px solid var(--color-background-border); border-radius: 0.25rem; background-color: var(--color-background-secondary); color: var(--color-foreground-primary); font-size: var(--font-size--small); cursor: pointer;">
       {% for item in versions %}
-      <option value="{{ item.url }}" {% if item.name == current_version %}selected{% endif %}>
-        {{ item.name }}{% if item.name == current_version %} (current){% endif %}
+      <option value="{{ item.url }}" {% if item == current_version %}selected{% endif %}>
+        {{ item.name }}{% if item == current_version %} (current){% endif %}
       </option>
       {% endfor %}
     </select>