fix: resolve all linting errors and type issues

- Remove unused setShowOfflineIndicator calls
- Remove unused areAllRelaysLocal import
- Fix duplicate key 'failedRelays' in console.log
- Replace 'any' types with proper HighlightEvent interface
- Add eslint-disable comments for intentionally excluded useEffect dependencies
- All linting errors resolved, type checks pass

src/hooks/useArticleLoader.ts

@@ -315,6 +315,9 @@ export function useArticleLoader({
     return () => {
       mountedRef.current = false
     }
+    // Dependencies intentionally excluded to prevent re-renders when relay/eventStore state changes
+    // This fixes the loading skeleton appearing when going offline (flight mode)
+    // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [
     naddr,
     previewData

src/hooks/useExternalUrlLoader.ts

@@ -165,6 +165,9 @@ export function useExternalUrlLoader({
     return () => {
       mountedRef.current = false
     }
+    // Dependencies intentionally excluded to prevent re-renders when relay/eventStore state changes
+    // This fixes the loading skeleton appearing when going offline (flight mode)
+    // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [
     url,
     cachedUrlHighlights