fix: restore original Ask-AI implementation

Rewrote ask-ai.js to match the original working implementation
from commit 95cee69, using simple functions instead of class-based
approach for better OAuth app integration.

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

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

my-blog/templates/base.html

@@ -49,7 +49,7 @@
                     </a>
                 </div>
                 <div class="header-actions">
-                    <button class="ask-ai-btn" onclick="BlogAI.toggle()" id="askAiButton">
+                    <button class="ask-ai-btn" onclick="toggleAskAI()" id="askAiButton">
                         <span class="ai-icon icon-ai"></span>
                         ai
                     </button>