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>

src/pages/SettingsPage.jsx

@@ -8,6 +8,7 @@ import {
   changePassword,
   updateProfile,
   updateReminderSettings,
+  sendReminderTest,
 } from '../syncService.js';
 import { exportJournalDocx, printJournalPdf } from '../utils/journalExport.js';
 
@@ -120,11 +121,20 @@ export default function SettingsPage() {
     window.setTimeout(() => setPodcastNameSaved(false), 2500);
   };
 
+  const [reminderTest, setReminderTest] = useState({ busy: false, ok: false, message: '' });
+  const testReminder = async () => {
+    setReminderTest({ busy: true, ok: false, message: '' });
+    const result = await sendReminderTest({ ntfyTopic: reminderForm.ntfyTopic, ntfyUrl: reminderForm.ntfyUrl });
+    setReminderTest(result.ok
+      ? { busy: false, ok: true, message: 'Sent. Check your ntfy app or the topic page in a browser.' }
+      : { busy: false, ok: false, message: result.error ?? 'Could not send the test.' });
+  };
+
   const submitReminderSettings = async (e) => {
     e.preventDefault();
     setReminderError('');
     setReminderBusy(true);
-    const result = await updateReminderSettings(reminderForm);
+    const result = await updateReminderSettings({ ...reminderForm, reminderTz: Intl.DateTimeFormat().resolvedOptions().timeZone });
     setReminderBusy(false);
     if (!result.ok) {
       setReminderError(result.error ?? 'Failed to save reminder settings.');
@@ -334,13 +344,26 @@ export default function SettingsPage() {
             </label>
             {reminderError && <p className="text-sm text-[var(--r-danger,#b42318)]">{reminderError}</p>}
             {reminderSaved && <p className="text-sm text-[var(--r-accent)]">Saved.</p>}
-            <button
-              type="submit"
-              disabled={reminderBusy}
-              className="rounded-full bg-[var(--r-accent)] px-5 py-2 text-sm font-medium text-[var(--r-on)] transition hover:opacity-90 disabled:cursor-not-allowed disabled:opacity-50"
-            >
-              {reminderBusy ? 'Saving…' : 'Save'}
-            </button>
+            {reminderTest.message && (
+              <p role="status" className={`text-sm ${reminderTest.ok ? 'text-[var(--r-accent)]' : 'text-[var(--r-danger,#b42318)]'}`}>{reminderTest.message}</p>
+            )}
+            <div className="flex flex-wrap items-center gap-3">
+              <button
+                type="submit"
+                disabled={reminderBusy}
+                className="rounded-full bg-[var(--r-accent)] px-5 py-2 text-sm font-medium text-[var(--r-on)] transition hover:opacity-90 disabled:cursor-not-allowed disabled:opacity-50"
+              >
+                {reminderBusy ? 'Saving…' : 'Save'}
+              </button>
+              <button
+                type="button"
+                onClick={testReminder}
+                disabled={reminderTest.busy || !reminderForm.ntfyTopic.trim()}
+                className="rounded-full border border-[var(--r-line)] px-5 py-2 text-sm font-medium transition hover:bg-black/5 disabled:cursor-not-allowed disabled:opacity-50"
+              >
+                {reminderTest.busy ? 'Sending…' : 'Send test notification'}
+              </button>
+            </div>
           </form>
         </section>