Harden platform security, reliability, and CI after full audit.

Close deployment IDOR and gate stub payment endpoints, add production
secret validation, health probes, Redis-backed build progress, GitHub
Actions CI, expanded tests, billing/k8s refactors, and ops runbooks.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/components/ui/button.tsx

@@ -0,0 +1,24 @@
+import clsx from 'clsx';
+import type { ButtonHTMLAttributes } from 'react';
+
+type ButtonVariant = 'primary' | 'secondary' | 'danger' | 'ghost';
+
+const variantClass: Record<ButtonVariant, string> = {
+  primary: 'btn-primary',
+  secondary: 'btn-secondary',
+  danger: 'btn-danger',
+  ghost: 'btn-ghost',
+};
+
+export function Button({
+  variant = 'primary',
+  className,
+  children,
+  ...props
+}: ButtonHTMLAttributes<HTMLButtonElement> & { variant?: ButtonVariant }) {
+  return (
+    <button type="button" className={clsx(variantClass[variant], className)} {...props}>
+      {children}
+    </button>
+  );
+}