The parent template is hidden from the calendar listing, but the
recurrence service was only generating children starting from the
second occurrence. Now generates a child for the parent's own start
date so the first occurrence is always visible.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
model_dump() includes None values for optional RecurrenceRule fields.
When serialized to JSON, these become explicit nulls (e.g. "weekday": null).
The recurrence service then does int(None) which raises TypeError.
Fix: strip None values when serializing rule to JSON, and add defensive
None handling in recurrence service for all rule.get() calls.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>