Clean up debug logging and fix compiler warnings

- Remove non-critical debug logs from backend CalDAV parsing
- Remove all-day event debug logs from frontend components
- Fix unused variable warnings with underscore prefixes
- Keep essential logging while reducing noise

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

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

frontend/src/components/week_view.rs

@@ -348,6 +348,7 @@ pub fn week_view(props: &WeekViewProps) -> Html {
         })
     };
 
+
     html! {
         <div class="week-view-container">
             // Header with weekday names and dates