refactor(frontend): finish shadcn→custom primitive migration (green build)

- Remove tw-animate-css import + dead src/components/ui shadcn tree
- Convert 7 orphaned components (moderation, analysis, guild-selector,
  voice/activity-timeline, shared/empty+error) to new primitives
- Add missing moderation/view.tsx; analysis uses SearchPanel directly
- globals.css now uses new signal-driven ops-console tokens
- tsc --noEmit clean, next build green (11 routes), local smoke 200

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

@@ -1,21 +1,18 @@
 import { AlertCircle, RefreshCw } from "lucide-react";
-
-import { Button } from "@/components/ui/button";
+import { Button } from "@/components/primitives/button";
 
 interface ErrorStateProps {
   message: string;
   onRetry?: () => void;
 }
 
-/**
- * Consistent error state for data-fetching pages.
- * Shows the error message with an optional retry button.
- */
 export function ErrorState({ message, onRetry }: ErrorStateProps) {
   return (
     <div className="flex flex-col items-center justify-center py-20 text-center">
-      <AlertCircle className="size-10 text-destructive mb-3" />
-      <p className="text-sm text-muted-foreground mb-4 max-w-sm">{message}</p>
+      <AlertCircle className="size-10 text-[var(--color-vermilion)] mb-3" />
+      <p className="text-sm text-[var(--color-ink-soft)] mb-4 max-w-sm">
+        {message}
+      </p>
       {onRetry && (
         <Button variant="outline" onClick={onRetry}>
           <RefreshCw className="size-4 mr-2" />