Record Streak, Grace Hour and Reminder decisions

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

GLOSSARY.md

@@ -81,4 +81,20 @@ The per-Mode list of Sessions with date, Plan, duration and Set Logs.
 
 **Streak**:
 A single, subtle, Duolingo-style daily streak shared by both Modes: consecutive days with at least one
-complete Session in either Mode, however short. Incomplete Sessions do not count.
+complete Session in either Mode, however short. Incomplete Sessions do not count. Shown as a small 🔥
+and count in the top bar (grey until today is done); tapping it opens current/longest Streak and a
+month calendar. Protected by Streak Freezes and the Grace Hour.
+
+**Streak Day**:
+The day a complete Session counts for. Normally its calendar day, except during the Grace Hour.
+
+**Grace Hour**:
+00:00–01:00. A Session completed then counts for the previous day if that day has no complete Session
+yet; otherwise it counts for the current day.
+
+**Streak Freeze**:
+A saved token that is used automatically to cover a missed day so the Streak survives.
+
+**Reminder**:
+A local notification sent only if no complete Session exists for the current Streak Day. Two by
+default (19:00 and a late-night one); times and on/off are adjustable in Settings.