test(11-05): RED — CR-01 custom alarm round-trip

- expand.test.ts: 3 new tests asserting reminderIsCustom:true for
  absolute DATE-TIME trigger and multi-VALARM, false for relative preset
- EventForm.test.tsx: 3 new tests asserting __custom__ picker init,
  'Custom (kept)' option visibility, and payload omits reminderLeadMinutes
- Fixtures: absolute-alarm.ics (DATE-TIME VALARM), multi-alarm.ics (2 VALARMs)
- All 6 new tests FAIL (RED): reminderIsCustom field not yet on interface

apps/api/tests/broker/expand.test.ts

@@ -310,6 +310,85 @@ describe('expandOccurrences', () => {
     });
   });
 
+  describe('reminderIsCustom — CR-01 (Phase 11 Plan 05)', () => {
+    it('absolute DATE-TIME VALARM trigger yields reminderIsCustom:true and reminderLeadMinutes:null', () => {
+      // Apple Calendar default all-day alarm style: TRIGGER;VALUE=DATE-TIME:...
+      // Before the fix, expand.ts maps {kind:'custom'} to null and does NOT set reminderIsCustom.
+      // This test MUST FAIL before the fix (no reminderIsCustom field on CalendarOccurrence).
+      const rawVevent = loadFixture('absolute-alarm.ics');
+      const windowStart = new Date('2026-12-01T00:00:00Z');
+      const windowEnd = new Date('2027-01-01T00:00:00Z');
+
+      const occurrences = expandOccurrences(
+        rawVevent,
+        windowStart,
+        windowEnd,
+        1,
+        'My Calendar',
+        1,
+        null,
+        '#4A90D9',
+        false,
+      );
+
+      expect(occurrences.length).toBe(1);
+      const occ = occurrences[0];
+      // reminderIsCustom MUST be true (absolute DATE-TIME trigger)
+      expect((occ as Record<string, unknown>).reminderIsCustom).toBe(true);
+      // reminderLeadMinutes MUST be null (cannot reduce custom to a lead)
+      expect(occ.reminderLeadMinutes).toBeNull();
+    });
+
+    it('multiple VALARMs yield reminderIsCustom:true and reminderLeadMinutes:null', () => {
+      // Outlook/Apple sometimes produce two VALARMs — classifyValarms returns {kind:'custom'}
+      const rawVevent = loadFixture('multi-alarm.ics');
+      const windowStart = new Date('2026-12-01T00:00:00Z');
+      const windowEnd = new Date('2027-01-01T00:00:00Z');
+
+      const occurrences = expandOccurrences(
+        rawVevent,
+        windowStart,
+        windowEnd,
+        1,
+        'My Calendar',
+        1,
+        null,
+        '#4A90D9',
+        false,
+      );
+
+      expect(occurrences.length).toBe(1);
+      const occ = occurrences[0];
+      expect((occ as Record<string, unknown>).reminderIsCustom).toBe(true);
+      expect(occ.reminderLeadMinutes).toBeNull();
+    });
+
+    it('single relative preset VALARM yields reminderIsCustom:false', () => {
+      // A normal -PT15M DURATION trigger should NOT be flagged as custom
+      const rawVevent = loadFixture('weekly-dst.ics');
+      const windowStart = new Date('2026-03-01T00:00:00Z');
+      const windowEnd = new Date('2026-03-15T00:00:00Z');
+
+      const occurrences = expandOccurrences(
+        rawVevent,
+        windowStart,
+        windowEnd,
+        1,
+        'My Calendar',
+        1,
+        null,
+        '#4A90D9',
+        false,
+      );
+
+      // weekly-dst.ics has no VALARM — reminderIsCustom should be false
+      expect(occurrences.length).toBeGreaterThan(0);
+      for (const occ of occurrences) {
+        expect((occ as Record<string, unknown>).reminderIsCustom).toBe(false);
+      }
+    });
+  });
+
   describe('Cross-contract: expand output → Temporal.ZonedDateTime.from (regression guard)', () => {
     it('timed event start/end strings from weekly-dst.ics parse via Temporal.ZonedDateTime.from without throwing', () => {
       // This is the integration test that was missing. It takes the actual serializeTime output

apps/api/tests/fixtures/absolute-alarm.ics

@@ -0,0 +1,14 @@
+BEGIN:VCALENDAR
+VERSION:2.0
+PRODID:-//Apple Calendar//NONSGML Version 1//EN
+BEGIN:VEVENT
+UID:absolute-alarm-test@familysync.test
+DTSTART;VALUE=DATE:20261215
+SUMMARY:Holiday Party
+BEGIN:VALARM
+ACTION:DISPLAY
+DESCRIPTION:Reminder
+TRIGGER;VALUE=DATE-TIME:20261214T140000Z
+END:VALARM
+END:VEVENT
+END:VCALENDAR

apps/api/tests/fixtures/multi-alarm.ics

@@ -0,0 +1,20 @@
+BEGIN:VCALENDAR
+VERSION:2.0
+PRODID:-//Outlook//NONSGML Version 1//EN
+BEGIN:VEVENT
+UID:multi-alarm-test@familysync.test
+DTSTART:20261215T100000Z
+DTEND:20261215T110000Z
+SUMMARY:Team Meeting
+BEGIN:VALARM
+ACTION:DISPLAY
+DESCRIPTION:Reminder 1
+TRIGGER:-PT15M
+END:VALARM
+BEGIN:VALARM
+ACTION:DISPLAY
+DESCRIPTION:Reminder 2
+TRIGGER:-PT5M
+END:VALARM
+END:VEVENT
+END:VCALENDAR