Fix off-day med reminders and add medication editing

Scheduler: check_nagging() now calls _is_med_due_today() before creating
on-demand schedules or processing existing ones — prevents nagging
for specific_days / every_n_days meds on days they are not scheduled.

Web client: add Edit button (pencil icon) on each medication card linking
to /dashboard/medications/[id]/edit — new page pre-populates the full
form (name, dosage, unit, frequency, times, days, interval, notes)
and submits PUT /api/medications/:id on save.

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

synculous-client/src/app/dashboard/medications/page.tsx

@@ -3,7 +3,7 @@
 import { useEffect, useState, useMemo } from 'react';
 import { useRouter } from 'next/navigation';
 import api from '@/lib/api';
-import { PlusIcon, CheckIcon, PillIcon, ClockIcon, TrashIcon } from '@/components/ui/Icons';
+import { PlusIcon, CheckIcon, PillIcon, ClockIcon, TrashIcon, EditIcon } from '@/components/ui/Icons';
 import Link from 'next/link';
 import PushNotificationToggle from '@/components/notifications/PushNotificationToggle';
 
@@ -380,12 +380,20 @@ export default function MedicationsPage() {
                         <p className="text-gray-400 dark:text-gray-500 text-sm mt-1">Times: {med.times.join(', ')}</p>
                       )}
                     </div>
-                    <button
-                      onClick={() => handleDelete(med.id)}
-                      className="text-red-500 dark:text-red-400 p-2"
-                    >
-                      <TrashIcon size={18} />
-                    </button>
+                    <div className="flex items-center gap-1">
+                      <Link
+                        href={`/dashboard/medications/${med.id}/edit`}
+                        className="text-gray-400 dark:text-gray-500 hover:text-indigo-600 dark:hover:text-indigo-400 p-2"
+                      >
+                        <EditIcon size={18} />
+                      </Link>
+                      <button
+                        onClick={() => handleDelete(med.id)}
+                        className="text-red-500 dark:text-red-400 p-2"
+                      >
+                        <TrashIcon size={18} />
+                      </button>
+                    </div>
                   </div>
 
                   {/* Adherence */}