refactor(settings): reorganize api-keys section into folder

- Move api-keys-section.tsx into api-keys/ folder
- Move child components (api-key-field, authentication-status-display, security-notice) into api-keys/
- Move custom hook (use-api-key-management) into api-keys/hooks/
- Move config (api-provider-config) into api-keys/config/
- Update import paths in use-api-key-management.ts
- Update settings-view.tsx to import from new location
- All TypeScript diagnostics passing
- Improves code organization and maintainability

app/src/components/views/settings-view/api-keys/security-notice.tsx

@@ -0,0 +1,21 @@
+import { AlertCircle } from "lucide-react";
+
+interface SecurityNoticeProps {
+  title?: string;
+  message?: string;
+}
+
+export function SecurityNotice({
+  title = "Security Notice",
+  message = "API keys are stored in your browser's local storage. Never share your API keys or commit them to version control.",
+}: SecurityNoticeProps) {
+  return (
+    <div className="flex items-start gap-3 p-4 rounded-lg bg-yellow-500/10 border border-yellow-500/20">
+      <AlertCircle className="w-5 h-5 text-yellow-500 mt-0.5 shrink-0" />
+      <div className="text-sm">
+        <p className="font-medium text-yellow-500">{title}</p>
+        <p className="text-yellow-500/80 text-xs mt-1">{message}</p>
+      </div>
+    </div>
+  );
+}