fix: seperate scheduler executors

[uwwint]

Description

seperate scheduler executors

Checklist

• I have commented my code, particularly in hard-to-understand areas
• I have added unit / integration tests that prove my fix is effective or that my feature works
• I have run all tests locally and they pass
• I have updated the documentation (if applicable)
• For any new secrets, I have updated the shared spreadsheet and the GitHub Secrets.

[Copilot]

Pull request overview

This PR separates APScheduler execution pools so email-queue work and other scheduled tasks run on dedicated single-worker threadpool executors, reducing the risk of long-running work impacting the main asyncio scheduler loop.

Changes:

• Add a new SCHEDULED_TASK_EXECUTOR and configure it as a single-worker threadpool executor.
• Route non-email scheduled jobs to SCHEDULED_TASK_EXECUTOR and email-queue jobs to EMAIL_QUEUE_EXECUTOR.
• Add/adjust job wrapper functions and tests to validate executor routing.

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
uv.lock	Bumps locked project version to 1.1.2.
tests/scheduled_tasks/test_scheduler.py	Extends scheduler tests to assert executor presence and correct routing of jobs.
scheduled_tasks/tasks.py	Routes email notification delivery jobs to the email executor and adds synchronous “*_job” wrappers around async tasks.
scheduled_tasks/scheduler.py	Introduces and wires the new SCHEDULED_TASK_EXECUTOR threadpool executor.
run_scheduler.py	Updates job registration to use the dedicated executors and the new “*_job” wrappers.