fix: remove isMounted from useEffect dependencies

- isMounted is a stable function from useMountedState and shouldn't be in deps
- Including it was preventing effects from running correctly
- Fixes issue where articles wouldn't load (stuck on spinner)

src/hooks/useArticleLoader.ts

@@ -116,6 +116,7 @@ export function useArticleLoader({
     
     loadArticle()
     // Intentionally excluding setter functions from dependencies to prevent race conditions
+    // isMounted is a stable function and doesn't need to be in dependencies
     // eslint-disable-next-line react-hooks/exhaustive-deps
-  }, [naddr, relayPool, settings, isMounted])
+  }, [naddr, relayPool, settings])
 }

src/hooks/useExternalUrlLoader.ts

@@ -150,8 +150,9 @@ export function useExternalUrlLoader({
     
     loadExternalUrl()
     // Intentionally excluding setter functions from dependencies to prevent race conditions
+    // isMounted is a stable function and doesn't need to be in dependencies
     // eslint-disable-next-line react-hooks/exhaustive-deps
-  }, [url, relayPool, eventStore, cachedUrlHighlights, isMounted])
+  }, [url, relayPool, eventStore, cachedUrlHighlights])
 
   // Keep UI highlights synced with cached store updates without reloading content
   useEffect(() => {