perf(react-doctor): fix compiler-blocking patterns, raise score 72→81

Replace sync setState-in-effect with keyed remount and render-derived patterns in app, error-display, topbar-edit-modal, catalog-filters; use useCurrentTime() instead of Date.now() in hot paths; fix conditional hooks, passive scroll listeners, lodash path imports.

src/hooks/use-state-string.ts

@@ -1,6 +1,6 @@
 import { useMemo } from 'react';
 import { useClientsStates, useSubplebbit, useSubplebbitsStates } from '@plebbit/plebbit-react-hooks';
-import { debounce } from 'lodash';
+import debounce from 'lodash/debounce';
 
 interface CommentOrSubplebbit {
   state?: string;