chore(repo): adopt vouch with issue based workflow and require for PRs (#3022)

Adopting [https://github.com/mitchellh/vouch](vouch) so we can help
potential contributors by requiring a conversation before they can
submit a PR. Too many contributors have been skipping the conversation
part of contributing to an OSS repo and skipping right ahead to
submitting PRs
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CONTRIBUTING.md

@@ -223,6 +223,19 @@ See the [Job Catalog](./references/job-catalog/README.md) file for more.
 4. Navigate to your trigger.dev instance ([http://localhost:3030](http://localhost:3030/)), to see the jobs.
    You can use the test feature to trigger them.
 
+## Getting vouched (required before opening a PR)
+
+We use [vouch](https://github.com/mitchellh/vouch) to manage contributor trust. **PRs from unvouched users are automatically closed.**
+
+Before you open your first pull request, you need to be vouched by a maintainer. Here's how:
+
+1. Open a [Vouch Request](https://github.com/triggerdotdev/trigger.dev/issues/new?template=vouch-request.yml) issue.
+2. Tell us what you'd like to work on and share any relevant background.
+3. A maintainer will review your request and vouch for you by commenting on the issue.
+4. Once vouched, your PRs will be accepted normally.
+
+If you're unsure whether you're already vouched, go ahead and open a PR — the check will tell you.
+
 ## Making a pull request
 
 **If you get errors, be sure to fix them before committing.**