update gh workflow to create PR when ai docs are affected

[aswamy]

TL;DR

Changed the GitHub workflow to create pull requests for AI documentation updates instead of directly pushing to main.

What changed?

• Modified the update-latest.yml workflow to create a pull request for changes instead of pushing directly to main
• Added branch creation with timestamp-based naming (update-ai-docs-YYYYMMDD-HHMMSS)
• Configured the workflow to use GitHub CLI to create a pull request with a descriptive title and body
• Updated the git configuration to use the standard GitHub Actions bot identity

How to test?

1. Trigger the workflow manually or wait for its scheduled run
2. Verify that a new pull request is created when there are changes to the AI documentation
3. Confirm the PR contains the expected changes to ai/liquid.mdc and data/latest.json
4. Check that the PR has the correct title and description

Example run: https://github.com/Shopify/theme-liquid-docs/actions/runs/16328413540/job/46124461065
Example PR created: #1006
⚠️ NOTE: It also contains the file in this PR since it branches off of main. You can ignore this commit in that PR, only see the changes to ai/liquid.mdc and data/latest.json

Why make this change?

This change improves the workflow by creating pull requests instead of direct commits to main, which:

• Provides better visibility into documentation updates
• Allows for review before changes are merged
• Creates a clearer history of documentation updates
• Follows best practices for repository management by avoiding direct pushes to the main branch

[aswamy]

• update gh workflow to create PR when ai docs are affected #1004 👈 (View in Graphite)
• main

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[karreiro]

Thank you for this PR, @aswamy!

Since we're aiming to create a pull request now, do you think we should change what triggers this workflow?

If we leave it as is, it seems like a new PR would be created on every commit, including when we merge the data/latest.json PR itself.

Maybe we could set this workflow to be triggered manually instead, or set the revision value using a different approach to prevent the creation of too many PRs. What do you think?

[aswamy]

If we leave it as is, it seems like a new PR would be created on every commit, including when we merge the data/latest.json PR itself.

Wouldn't this only be created if we merge to main? Also this only creates the PR IF it needs to be created since we have the if [[ -n "$(git status --porcelain)" ]]; then line.

I guess if we forget to merge one, we can see a lot of these PRs pile up 🤔

[karreiro]

Wouldn't this only be created if we merge to main? Also this only creates the PR IF it needs to be created since we have the if [[ -n "$(git status --porcelain)" ]]; then line.

As soon as we merge a PR updating data/latest.json, I believe the value in the line below will change and the workflow will create a new PR:

theme-liquid-docs/.github/workflows/update-latest.yml

Line 24 in 3b5f02e

echo -e { \"revision\": \"$(git rev-parse HEAD)\" }\\n > data/latest.json

Am I missing something?

@aswamy, please, feel free to proceed with the merge, if you'd like to validate that assumption :)