Add /contacts and /calendar pages; email signature settings; v1.1.12

- /contacts: standalone page with hybrid contact list (submissions + manual entry), inline edit, search, archive
- /calendar: monthly release scheduling calendar reading/writing podcast checklist episode dates
- /email settings: editable signature panel; signature persisted server-side and injected into outgoing emails
- Move contacts out of /admin panel (now links to /contacts route)
- Partial PATCH for contact submissions (name, notes, archived independently)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

server/email.js

@@ -350,9 +350,11 @@ export function buildContactAdminNotificationTemplate({
   }
 }
 
-export function buildAdminReplyTemplate({ recipientName, message }) {
+export function buildAdminReplyTemplate({ recipientName, message, signature }) {
   const safeRecipientName = escapeHtml(recipientName || 'friend')
   const safeMessage = escapeHtml(message).replace(/\n/g, '<br/>')
+  const sig = typeof signature === 'string' && signature.trim() ? signature.trim() : 'Grace and peace,\nVerse by Verse with Nate'
+  const safeSig = escapeHtml(sig).replace(/\n/g, '<br/>')
   return `
     <div style="margin:0;padding:0;background-color:#f5f1e8;font-family:Georgia,serif;color:#201a10;">
       <table width="100%" cellpadding="0" cellspacing="0" border="0" role="presentation" style="background-color:#f5f1e8;">
@@ -369,7 +371,7 @@ export function buildAdminReplyTemplate({ recipientName, message }) {
                 <td style="padding:26px 24px 18px;">
                   <p style="margin:0 0 16px;font-family:Arial,sans-serif;font-size:16px;line-height:1.6;color:#201a10;">Hi ${safeRecipientName},</p>
                   <div style="margin:0 0 18px;font-family:Arial,sans-serif;font-size:15px;line-height:1.7;color:#201a10;">${safeMessage}</div>
-                  <p style="margin:0;font-family:Arial,sans-serif;font-size:15px;line-height:1.7;color:#201a10;">Grace and peace,<br/>Verse by Verse with Nate</p>
+                  <p style="margin:0;font-family:Arial,sans-serif;font-size:15px;line-height:1.7;color:#201a10;">${safeSig}</p>
                 </td>
               </tr>
               <tr>