Customise buttons in adminapprove step

[KBorm]

Note: Please fill out all relevant sections and remove irrelevant ones.

🔀 Purpose of this PR:

• Fixes a bug
• Updates for a new Moodle version
• Adds a new feature of functionality
• Improves or enhances existing features
• Refactoring: restructures code for better performance or maintainability
• Testing: add missing or improve existing tests
• Miscellaneous: code cleaning (without functional changes), documentation, configuration, ...

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📝 Description:

Please describe the purpose of this PR in a few sentences.

• What feature or bug does it address?
  Extends the adminapprove step by allowing the button labels to be customized

• Why is this change or addition necessary?
  We had a scenario where the default button texts cause confustion (proceeding meant stopping the course).
  This PR also improves usability because it is easier to see what you are actually confirming in that admin approve step.

• What is the expected behavior after the change?

1. existing admin steps display as before
2. no values set in adminapprove config means default behaviour
3. values set will override buttons in approvals page and in active workflow page for adminapprove step

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📋 Checklist

Please confirm the following (check all that apply):

• I have phpunit and/or behat tests that cover my changes or additions.
• Code passes the code checker without errors and warnings.
• Code passes the moodle-ci/cd pipeline on all supported Moodle versions or the ones the plugin supports.
• Code does not have var_dump() or var_export or any other debugging statements (or commented out code) that
  should not appear on the productive branch.
• Code only uses language strings instead of hard-coded strings.
• [(x)] If there are changes in the database: I updated/created the necessary upgrade steps in db/upgrade.php and
  updated the version.php.
• [(x)] If there are changes in javascript: I build new .min files with the grunt amd command.
• [(x)] If it is a Moodle update PR: I read the release notes, updated the version.php and the CHANGES.md.
  I ran all tests thoroughly checking for errors. I checked if bootstrap had any changes/deprecations that require
  changes in the plugins UI.

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🔍 Related Issues

• Related to #[IssueNumber]

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🧾📸🌐 Additional Information (like screenshots, documentation, links, etc.)

Any other relevant information.

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[bluetom]

A cool thing, thank you for your work!
I’ll have a closer look at the code in the next few days.

[bluetom]

Could you change the version number in version.php to 2025102300.01?
Like Moodle HQ I only change the date for major updates.
Thank you very much,
Thomas

[KBorm]

Yes, it is ok.
But I do not know how to update the version.php in the pull request ;-)

[KBorm]

Oh, I see. github did the job for me :-)