Improve Spotless Integration: Enhance `CI Workflow`

[YongGoose]

In the last PR, there was a suggestion that our CI could be more helpful when code style checks fail.

• optimize: Apply Spotless with Palantir Java Format #7223 (comment)

Currently, the CI fails silently without guiding contributors on how to fix the issue.
To improve the developer experience, I propose two enhancements to the CI workflow:

1. Prompt contributors when formatting fails

If code formatting does not meet expectations, the workflow should print a clear message such as:

Code style check failed. Please run `mvn spotless:apply` locally to fix formatting issues.

This behavior is common in projects like Dubbo and helps reduce confusion for new contributors.

• https://github.com/apache/dubbo/blob/7b34ad9c8640480124c5907de9a76460171921e1/.github/workflows/build-and-test-pr.yml#L63-L67

2. Auto-format code and commit to PR

IMHO, It would be great if CI workflow to not only check formatting but also apply fixes via mvn spotless:apply and push them directly to the PR.

However, I'm not sure whether this is technically feasible. 😅
If anyone in the community has experience with this or knows more about it, your input would be greatly appreciated.

[YongGoose]

I plan to proceed with work based on the discussion below.

• Is it possible for CI to auto-format code and push fixes to a PR using Spotless? diffplug/spotless#2476

[YongGoose]

Decision:

The Spotless team is also aware of this feature, and there's an open issue to implement a way to notify users through comments.

• spotlessCheck could add comments and suggested fix to GitHub PR diffplug/spotless#655

I will implement that feature first, and then apply it to Seata.

[funky-eyes]

I hope this issue can be resolved. My habit is to save code first by committing it to prevent any loss. However, since I commit my code first, mvn spotless:apply becomes ineffective. This is extremely frustrating as it forces me to manually format my code segments again.

[YongGoose]

I hope this issue can be resolved. My habit is to save code first by committing it to prevent any loss. However, since I commit my code first, mvn spotless:apply becomes ineffective. This is extremely frustrating as it forces me to manually format my code segments again.

Actually, I think the most efficient way to solve this is to remove the scope limitation in Spotless.
Adding this new feature to Spotless and applying it to Seata will probably take at least a month.

I believe it's time to consider some trade-offs.
What do you think?