Fix plan days with no chapters, add a way out of ink mode, harden ntfy reminders

Plans can no longer have more days than chapters (existing ones heal), and
opening a plan never strands the Reader on an empty day. The Reader shows
Done drawing while inking (Escape also exits). Reminders use the user's own
timezone, send within a 3 hour grace window, and Settings has a Send test
notification button.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

server/index.js

@@ -22,7 +22,7 @@ import {
   generateTotpSecret, totpKeyUri, verifyTotpToken,
   generateBackupCodes, hashBackupCodes, consumeBackupCode, generateTemporaryPassword,
 } from './auth.js';
-import { startReminderScheduler } from './reminders.js';
+import { startReminderScheduler, sendTestReminder, isValidTimeZone } from './reminders.js';
 import { registerBibleRoutes } from './bibleApi.js';
 
 // Shape returned to the client for the signed-in user (login, MFA verify, /auth/me).
@@ -236,6 +236,7 @@ app.patch('/api/auth/reminder-settings', requireAuth, (req, res) => {
     const ntfyTopic = String(req.body?.ntfyTopic ?? '').trim();
     const ntfyUrl = String(req.body?.ntfyUrl ?? '').trim();
     const reminderTime = String(req.body?.reminderTime ?? '').trim();
+    const reminderTz = isValidTimeZone(req.body?.reminderTz) ? String(req.body.reminderTz) : null;
 
     if (ntfyTopic && !/^[A-Za-z0-9_-]{1,64}$/.test(ntfyTopic)) {
       return res.status(400).json({ error: 'Topic can only contain letters, numbers, "-" and "_".' });
@@ -255,6 +256,7 @@ app.patch('/api/auth/reminder-settings', requireAuth, (req, res) => {
       ntfyTopic: ntfyTopic || null,
       reminderTime: reminderTime || null,
       reminderEnabled,
+      reminderTz,
     });
     res.json({
       reminderEnabled, ntfyUrl: ntfyUrl || null, ntfyTopic: ntfyTopic || null, reminderTime: reminderTime || null,
@@ -477,6 +479,33 @@ app.put('/api/reading-plans', requireAuth, (req, res) => {
   }
 });
 
+// POST /api/auth/reminder-test — sends a test notification to the topic in the request
+// body (so it can be tried before saving), or to the saved settings.
+const _lastReminderTest = new Map(); // userId -> timestamp, to keep test sends from being spammed
+app.post('/api/auth/reminder-test', requireAuth, async (req, res) => {
+  const userId = req.session.userId;
+  if (Date.now() - (_lastReminderTest.get(userId) ?? 0) < 5000) {
+    return res.status(429).json({ error: 'Wait a few seconds before sending another test.' });
+  }
+  _lastReminderTest.set(userId, Date.now());
+  const saved = getUserById(userId);
+  const ntfyTopic = String(req.body?.ntfyTopic ?? saved?.ntfyTopic ?? '').trim();
+  const ntfyUrl = String(req.body?.ntfyUrl ?? saved?.ntfyUrl ?? '').trim();
+  if (!ntfyTopic) return res.status(400).json({ error: 'Enter a topic first.' });
+  if (!/^[A-Za-z0-9_-]{1,64}$/.test(ntfyTopic)) {
+    return res.status(400).json({ error: 'Topic can only contain letters, numbers, "-" and "_".' });
+  }
+  if (ntfyUrl && !/^https?:\/\/.{1,200}$/.test(ntfyUrl)) {
+    return res.status(400).json({ error: 'Server URL must start with http:// or https://.' });
+  }
+  try {
+    await sendTestReminder({ ntfyTopic, ntfyUrl });
+    res.json({ ok: true });
+  } catch (err) {
+    res.status(502).json({ error: err.message });
+  }
+});
+
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