Remove 'Read this first' alert from Help page

The amber state-actor warning at the top of /help duplicated copy that
now lives in the Fast Mode section of the Activist Guide and would read
as overly conservative once Private Mode campaigns exist. The two large
guide buttons below it already point readers at the long-form content.

src/pages/HelpPage.tsx

@@ -1,8 +1,7 @@
 import { useSeoMeta } from '@unhead/react';
-import { AlertTriangle, ChevronRight, HandHeart, HelpCircle, Megaphone, Shield } from 'lucide-react';
+import { ChevronRight, HandHeart, HelpCircle, Megaphone, Shield } from 'lucide-react';
 import { Link } from 'react-router-dom';
 
-import { Alert, AlertDescription, AlertTitle } from '@/components/ui/alert';
 import { useAppContext } from '@/hooks/useAppContext';
 import { useLayoutOptions } from '@/contexts/LayoutContext';
 import { PageHeader } from '@/components/PageHeader';
@@ -22,23 +21,6 @@ export function HelpPage() {
     <main className="min-h-screen pb-16 sidebar:pb-0">
       <PageHeader title="Help" icon={<HelpCircle className="size-5" />} />
 
-      {/* Top-of-page disclaimer: first thing visitors see */}
-      <div className="px-4 pt-2">
-        <Alert className="border-amber-500/50 [&>svg]:text-amber-500">
-          <AlertTriangle className="size-4" />
-          <AlertTitle className="text-amber-700 dark:text-amber-400">Read this first</AlertTitle>
-          <AlertDescription className="text-foreground/80">
-            <p>
-              {config.appName} is recommended only for above-ground activism. Every donation
-              &mdash; given or received &mdash; is public on the Bitcoin blockchain and on Nostr. If
-              you or your donors require extreme privacy, including from state actors, additional
-              steps are required to protect yourself. Read the <strong>Donor Guide</strong> and{' '}
-              <strong>Activist Guide</strong> below before participating.
-            </p>
-          </AlertDescription>
-        </Alert>
-      </div>
-
       {/* Two large guide buttons */}
       <div className="px-4 pt-4 grid gap-3 sm:grid-cols-2">
         <GuideButton