Fix triage_labelled GHA workflow

[anoadragon453]

I got tired of this workflow failing when triaging issues.

The old workflow failed if the item was already on the board. This was partially fixed in #18755, which would skip the actions/add-to-project step if the issue was already on the board.

However, that meant that the second step now failed, as it now had an empty value for ${{ steps.add_project.outputs.itemId }}.

---

This PR rips out the add-to-project action (which doesn't handle an issue already being on a project) and our old hand-written code and replaces it with new manual code. I tried to look for another action to replace what we had and came across https://github.com/EndBug/project-fields. But that action doesn't support adding the issue to the project.

This new code was mostly written by AI (GPT-5). It was tested successfully in a separate repo to ensure it works (though I've since deleted the associated test project).

---

Just as before, issues are not moved out of the "Needs Info" column automatically, unless they are closed. I think it may make sense to move them to "Traiged", but that can be done in a separate PR.

Pull Request Checklist

• Pull request is based on the develop branch
• Pull request includes a changelog file. The entry should:
  • Be a short description of your change which makes sense to users. "Fixed a bug that prevented receiving messages from other servers." instead of "Moved X method from EventStore to EventWorkerStore.".
  • Use markdown where necessary, mostly for code blocks.
  • End with either a period (.) or an exclamation mark (!).
  • Start with a capital letter.
  • Feel free to credit yourself, by adding a sentence "Contributed by @github_username." or "Contributed by [Your Name]." to the end of the entry.
• Code style is correct (run the linters)