feat(fe): optimize error handling, state consistency, and WS feedback

- Add global SWR config with exponential backoff retry (swr-config.ts)
- Add ErrorBoundary component for React crash recovery (error-boundary.tsx)
- Standardize ErrorState onRetry on all 6 dashboard views (dashboard, media,
  messages, moderation, recordings, voice)
- Fix useAction: expose resetError + onError callback
- Refactor useSpeakers to SWR-backed state (was local useState) for
  consistent cache/revalidate semantics with other hooks
- Remove polling in useReview (15s refreshInterval); replace with
  useReviewWsSync subscribing to WS moderation_action events
- Extract hashUserId to lib/hash.ts (de-dup with ambient-canvas)
- WS context: add reconnect/error toast feedback via onStatusChange
- WS connection: expose reconnectAttemptCount getter

All typecheck + lint clean, Next 16 build passes.

services/frontend/src/components/shared/error-boundary.tsx

@@ -0,0 +1,56 @@
+"use client";
+
+import { Component, type ReactNode } from "react";
+import { ErrorState } from "./states";
+
+/**
+ * React error boundary — catches render/exception crashes in child trees
+ * (e.g. third-party lib throwing on unexpected payload shape) and surfaces
+ * a consistent ErrorState instead of unmounting the whole app shell.
+ *
+ * Usage: wrap leaf views in <ErrorBoundary><SomeView /></ErrorBoundary>.
+ */
+interface ErrorBoundaryProps {
+  children: ReactNode;
+  fallback?: (error: Error, reset: () => void) => ReactNode;
+  onReset?: () => void;
+}
+
+interface ErrorBoundaryState {
+  error: Error | null;
+}
+
+export class ErrorBoundary extends Component<
+  ErrorBoundaryProps,
+  ErrorBoundaryState
+> {
+  constructor(props: ErrorBoundaryProps) {
+    super(props);
+    this.state = { error: null };
+  }
+
+  static getDerivedStateFromError(error: Error): ErrorBoundaryState {
+    return { error };
+  }
+
+  reset = () => {
+    this.setState({ error: null });
+    this.props.onReset?.();
+  };
+
+  override render() {
+    if (!this.state.error) return this.props.children;
+
+    if (this.props.fallback) {
+      return this.props.fallback(this.state.error, this.reset);
+    }
+
+    return (
+      <ErrorState
+        title="Something went wrong"
+        error={this.state.error}
+        onRetry={this.reset}
+      />
+    );
+  }
+}

services/frontend/src/components/shared/index.ts

@@ -2,6 +2,7 @@ export { GuildChannelPicker } from "./guild-picker";
 export { MarkdownLite } from "./markdown";
 export { PageTransition } from "./page-transition";
 export { MetricTile, SectionHeader } from "./section";
+export { ErrorBoundary } from "./error-boundary";
 export {
   EmptyState,
   ErrorState,