Wire up mark_as_cancelled function in trigger cancellation flow

[coderabbitai]

Description

The mark_as_cancelled function was implemented in PR #464 to apply TTL cleanup logic for CANCELLED triggers, but it is not currently invoked anywhere in the production codebase.

Task

Either:

• Wire the function into the cancellation pathway where triggers are currently being cancelled
• Or remove the function if TTL behavior for CANCELLED triggers is not needed

Details

The function is located in state-manager/app/tasks/trigger_cron.py (lines 48-57) and correctly sets:

• trigger_status to TriggerStatusEnum.CANCELLED
• expires_at for TTL-based cleanup

To fix, locate where triggers are currently cancelled and replace direct status updates with a call to mark_as_cancelled(trigger, retention_days), ensuring retention_days is sourced from config.

Context

Related PR: #464
Original discussion: #464 (comment)

Requested by: @spa-raj

[Brijesh-Thakkar]

Hi @NiveditJain,
While you're reviewing my approach on issue #476, would it be alright if I start working on this one in the meantime?
Just want to make sure I’m aligned and not blocking anything.

Thanks!