Wire the snooze read into the Gatherer and honour it for reminders (#364)

The Gatherer now fills State.SnoozeUntil from store.SnoozedUntil instead
of nil, so a snooze finally reaches the gate. RemindDecisions gains the
one restraint check that applies to a reminder — quiet hours, presence
and cooldown are still bypassed, so "wake me 7" is unchanged. Reviewer:
the two tests in internal/loop/gate_test.go are the contract.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CGeSZxh1DCtRxmFVSYVGvJ

internal/loop/gate_test.go

@@ -273,7 +273,6 @@ func TestRemindersBypassEverySuppressor(t *testing.T) {
 // passes every due reminder straight through with no snooze check, so a snoozed
 // reminder fires anyway. The test below is what the contract asks for.
 func TestRemindersStillHonourSnooze(t *testing.T) {
-	t.Skip("snooze is not applied to reminders — RemindDecisions ignores SnoozeUntil, internal/loop/loop.go:120")
 
 	now := refTime()
 	s := State{
@@ -292,7 +291,6 @@ func TestRemindersStillHonourSnooze(t *testing.T) {
 // unit tests above pass while nothing can ever populate the map. This asserts
 // the Gatherer actually produces a snooze map.
 func TestGathererPopulatesSnoozeUntil(t *testing.T) {
-	t.Skip("Gatherer never populates SnoozeUntil, so snooze cannot suppress anything at runtime, internal/loop/gather.go:153")
 
 	ctx := context.Background()
 	st, err := store.Open(ctx, t.TempDir()+"/m.db")