Add upload email notifications with Seafile direct-upload watcher; v2.0.6

- Portal uploads send one email immediately (host, episode, passage,
  description, filenames) via Resend to NUGGETS_NOTIFY_EMAIL
- Seafile watcher polls /Episode Upload every 15 min for direct uploads
  and sends a notification for any new file not already seen via portal
- Files uploaded through the portal are marked seen so the watcher
  never sends a duplicate notification
- Credentials kept out of git: SEAFILE_TOKEN, SEAFILE_NUGGETS_REPO_ID,
  NUGGETS_NOTIFY_EMAIL now sourced from docker .env file

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

server/email.js

@@ -712,3 +712,55 @@ export async function sendStudyWeeklyDigestEmail(email, displayName, lessons, un
     console.error('[study-digest] send exception:', err)
   }
 }
+
+// ── Nuggets upload notifications ───────────────────────────────────────────
+
+export async function sendNuggetsUploadNotification({ to, source, hostName, episodeName, passage, description, filename, infoFile }) {
+  if (!process.env.RESEND_API_KEY) return
+  const resend = new Resend(process.env.RESEND_API_KEY)
+  const from = process.env.RESEND_FROM ?? DEFAULT_RESEND_FROM
+  const sourceLabel = source === 'portal' ? 'Upload Portal' : 'Direct to Seafile'
+  const subject = `New Nuggets Episode Upload: ${episodeName || filename}`
+
+  const bodyHtml = `
+    <p style="margin:0 0 16px;font-family:Arial,sans-serif;font-size:15px;color:#2c2417;">A new episode file has arrived in Seafile.</p>
+    <table style="width:100%;border-collapse:collapse;font-family:Arial,sans-serif;font-size:14px;color:#2c2417;">
+      <tr><td style="padding:6px 0;color:#7a7060;width:120px;">Source</td><td style="padding:6px 0;font-weight:600;">${escapeHtml(sourceLabel)}</td></tr>
+      ${hostName ? `<tr><td style="padding:6px 0;color:#7a7060;">Host</td><td style="padding:6px 0;">${escapeHtml(hostName)}</td></tr>` : ''}
+      ${episodeName ? `<tr><td style="padding:6px 0;color:#7a7060;">Episode</td><td style="padding:6px 0;font-weight:600;">${escapeHtml(episodeName)}</td></tr>` : ''}
+      ${passage ? `<tr><td style="padding:6px 0;color:#7a7060;">Passage</td><td style="padding:6px 0;">${escapeHtml(passage)}</td></tr>` : ''}
+      <tr><td style="padding:6px 0;color:#7a7060;">Audio File</td><td style="padding:6px 0;font-family:monospace;font-size:13px;">${escapeHtml(filename)}</td></tr>
+      ${infoFile ? `<tr><td style="padding:6px 0;color:#7a7060;">Info File</td><td style="padding:6px 0;font-family:monospace;font-size:13px;">${escapeHtml(infoFile)}</td></tr>` : ''}
+    </table>
+    ${description ? `<p style="margin:16px 0 0;font-family:Arial,sans-serif;font-size:14px;color:#2c2417;"><strong>Description:</strong><br/>${escapeHtml(description).replace(/\n/g, '<br/>')}</p>` : ''}
+  `
+
+  const textBody = [
+    `New Nuggets Episode Upload (${sourceLabel})`,
+    '',
+    hostName ? `Host: ${hostName}` : '',
+    episodeName ? `Episode: ${episodeName}` : '',
+    passage ? `Passage: ${passage}` : '',
+    `Audio File: ${filename}`,
+    infoFile ? `Info File: ${infoFile}` : '',
+    description ? `\nDescription:\n${description}` : '',
+  ].filter(Boolean).join('\n')
+
+  try {
+    const { error } = await resend.emails.send({
+      from,
+      to: [to],
+      subject,
+      text: textBody,
+      html: buildBrandedEmailHtml({
+        title: 'New Episode Upload',
+        eyebrow: 'Nuggets',
+        bodyHtml,
+        footerHtml: '<p style="margin:0;font-family:Arial,sans-serif;font-size:12px;color:#7a7060;">This notification was sent because a file was uploaded to the Nuggets Seafile library.</p>',
+      }),
+    })
+    if (error) console.error('[nuggets-notify] send error:', error)
+  } catch (err) {
+    console.error('[nuggets-notify] send exception:', err)
+  }
+}