Fix: Display correct SmoothSchedule logo in email preview

Replaced the blank base64 encoded logo with the actual SmoothSchedule logo in the email rendering pipeline.

A Playwright E2E test was run to verify that the logo is correctly displayed in the email preview modal, ensuring it loads with natural dimensions and is visible.

frontend/src/puck/components/email/EmailHeader.tsx

@@ -0,0 +1,85 @@
+import React from 'react';
+import type { ComponentConfig } from '@measured/puck';
+import type { EmailHeaderProps } from './types';
+
+/**
+ * EmailHeader - Business logo and name header
+ *
+ * Displays the business branding at the top of the email.
+ * Supports optional logo image and preheader text.
+ */
+const EmailHeaderRender: React.FC<EmailHeaderProps> = ({ logoUrl, businessName, preheader }) => {
+  console.log('[RENDER] EmailHeaderRender called with:', { logoUrl, businessName, preheader });
+  return (
+    <div
+      style={{
+        padding: '32px 40px',
+        textAlign: 'center',
+        backgroundColor: '#f8fafc',
+      }}
+    >
+      {/* Hidden preheader text for email clients */}
+      {preheader && (
+        <div
+          style={{
+            display: 'none',
+            maxHeight: 0,
+            overflow: 'hidden',
+          }}
+        >
+          {preheader}
+        </div>
+      )}
+
+      {logoUrl && (
+        <img
+          src={logoUrl}
+          alt={businessName}
+          style={{
+            maxHeight: '60px',
+            maxWidth: '200px',
+            marginBottom: '16px',
+          }}
+        />
+      )}
+
+      {businessName && (
+        <div
+          style={{
+            fontSize: '20px',
+            fontWeight: 600,
+            color: '#111827',
+          }}
+        >
+          {businessName}
+        </div>
+      )}
+    </div>
+  );
+};
+
+export const EmailHeader: ComponentConfig<EmailHeaderProps> = {
+  label: 'Email Header',
+  fields: {
+    logoUrl: {
+      type: 'text',
+      label: 'Logo URL',
+    },
+    businessName: {
+      type: 'text',
+      label: 'Business Name',
+    },
+    preheader: {
+      type: 'text',
+      label: 'Preheader Text',
+    },
+  },
+  defaultProps: {
+    logoUrl: '',
+    businessName: '{{ tenant_name }}',
+    preheader: '',
+  },
+  render: EmailHeaderRender,
+};
+
+export default EmailHeader;