feat: create add-to-triage.yml

[lumirlumir]

Prerequisites checklist

• I have read the contributing guidelines.

What is the purpose of this pull request?

Hi,

In this PR, I've created the add-to-triage.yml workflow. (You can find the guides for the reusable workflow here.)

FYI, This workflow is also triggered in this repository, as I used the on.issues and on.pull_request events.

Other repositories can use this workflow as well, since I included the workflow_call event.

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I've tested this workflow in my personal repository, and it works as expected except for the part where a token is required.

It means that the workflow is triggered when issues and pull requests are opened, reopened, or transferred.

What changes did you make? (Give an overview)

1. Create add-to-triage.yml workflow.
2. Create .gitignore
3. Create .editorconfig file, referring to https://github.com/eslint/markdown/blob/main/.editorconfig.

Related Issues

Ref: #4, #5

Is there anything you'd like reviewers to focus on?

There are a few prerequisites for this workflow to function as expected:

• Is PROJECT_BOT_TOKEN secret set at the organization level?
• Is the Needs Triage column set as the default for the "Triage" project board?
  • Ref: https://github.com/actions/add-to-project/tree/v1.0.2/?tab=readme-ov-file#setting-a-specific-status-or-column-name-to-the-project-item
  

It would be great if these items could be addressed before wrapping up this work!

[nzakas]

• Is PROJECT_BOT_TOKEN secret set at the organization level?

Yes.

• Is the Needs Triage column set as the default for the "Triage" project board?

Yes.

[nzakas]

LGTM. Leaving open for @lumirlumir to decide if it's ready for merge based on my comment.

[lumirlumir]

Thanks for checking! Everything looks good, so I'll go ahead and merge it. 👍