[scheduler] Timezone Issue 2: Use render timezone in nowUpdatedEveryMinute and date-generating selectors

[rita-codes]

• Locate nowUpdatedEveryMinute and any selector that generates “now”, “today”, or visible ranges.
• Make these selectors use the render timezone and the adapter to create dates in the render timezone.
• Factor out any duplicate logic into a shared helper like getNowInRenderTimezone(state, adapter).
• Add tests ensuring behavior stays the same for 'default' and changes appropriately when passing a specific timezone.