This PR does two things:

1. Fix the `"githubToken" length must be less than or equal to 100 characters long` error.

2. Make the messages more informative.

**For issues:**

> This issue has been automatically closed and locked.
> 
> Processing 3.x is no longer actively developed. Since January 2020, development moved to the Processing 4 repository.
> 
> If this issue is still relevant to Processing 4, we'd love to hear from you. Please open a new issue at:
> https://github.com/processing/processing4/issues/new/choose
> 
> Thank you for helping improve Processing

**For PRs:**

> This pull request has been automatically closed and locked.
> 
> Processing 3.x is no longer actively developed. Since January 2020, development moved to the Processing 4 repository.
>
> If you'd still like to contribute this work, please open an issue in the Processing 4 repository to discuss it first:
> https://github.com/processing/processing4/issues/new/choose
> 
> Thank you for your contribution.

Update workflow to close old issues and PRs

…kflow

Add workflow to redirect issues to Processing 4

> [!NOTE]
> this needs testing against the actual repository.

This PR fixes the following issue: `Error: Unhandled error: HttpError: Unable to create comment because issue is locked.`

See: https://github.com/processing/processing/actions/runs/29001253630

#### Summary of changes:

-   Skips commenting/locking on threads that are already locked (fixes the `HttpError: Unable to create comment because issue is locked` crash)
-   Wraps per-thread processing in try/catch so one failure doesn't abort the whole run
-   Closes PRs via `pulls.update` instead of `issues.update`
-   Adds a `concurrency` group to prevent overlapping runs
-   Handles labels returned as plain strings, not just objects
-   Breaks out of the loop once a thread is newer than the cutoff (list is already sorted) instead of just `continue`
-   Builds close messages via array + `join('\n')` instead of a template literal (avoids leading-whitespace indentation in the posted comment)

…on-locked-issues-1

Fix locked issue crash + robustness changes