fix: Improve viewport fix to avoid interfering with page initialization

Changed viewport fix approach to be less invasive:
- Removed document.body.style.height modification
- Use document.documentElement.offsetHeight instead
- Trigger resize event instead of modifying DOM
- Increased delay from 100ms to 150ms for better stability

This should prevent potential conflicts with channel loading and
other page initialization code.

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

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

app/templates/base.html

@@ -266,13 +266,14 @@
     <script>
         // Fix viewport corruption on Android PWA after page reload
         window.addEventListener('load', function() {
-            // Force viewport recalculation
+            // Force viewport recalculation without modifying body height
             setTimeout(() => {
                 window.scrollTo(0, 0);
-                // Force reflow
-                document.body.style.height = '100%';
-                void(document.body.offsetHeight);
-            }, 100);
+                // Force reflow using a less invasive method
+                void(document.documentElement.offsetHeight);
+                // Trigger resize event to recalculate layout
+                window.dispatchEvent(new Event('resize'));
+            }, 150);
         });
     </script>