[Zacgoose]

• JitterMinutes on a timer entry delays each firing by a fixed per-site share of that window, so apps on a shared plan stop starting the same work in the same minute
• The share is the same for every timer on a site, so a timer with at least the jitter of the one it follows never fires closer to it
• Clamped below the shortest gap between the cron's slots; startup and timezone reseeds keep a slot that is still inside its window
• Start and CollectDue split out of the loop so a test can run the real service: timer file, CraftTZ, jitter and seeding, with dispatch left out
• SetTimezone takes the time internally so the warmup's runtime switch can be replayed
• Pins TZOffset vs ApplyTZOffset, once-per-night jittered firing across both DST changes, restarts inside and after the jitter window, and the warmup switch