phpstorm - Prefer to store generated hints in source-tree

[totten]

Overview

Revises the recently-added extension, phpstorm, to change the preferred location for generated hints. This should improve the range of compatible environments.

cc @eileenmcnaughton @colemanw

Before

• Store dynamic metadata in [civicrm.files]/.phpstorm.meta.php/*.php
• Store static metadata in tools/extensions/phpstorm/.phpstorm.meta.php

After

• Store all metadata files in the same folder
• Choose the folder from a list:
  • tools/extensions/phpstorm/.phpstorm.meta.php/*.php (default/preferred)
  • [civicrm.files]/.phpstorm.meta.php/*.php (default/fallback)
  • CIVICRM_PHPSTORM_METADATA (manual override via civicrm.settings.php)

Technical Details

These are decent folders - but not universal/awesome. Compare:

• [civicrm.files] is always writable by PHP. But it's not always visible to PhpStorm.
• tools/extensions/phpstorm/ is always visible to PhpStorm. But PHP is not always able to write it.

If you load the patch on an existing alpha build where the extension has been previously installed, then you may have two copies of .phpstorm.meta.php. This should be cleaned up by uninstalling/reinstalling the extension. (It just didn't seem worthwhile to write an upgrade task for something that's only affects the same alpha.)

[civibot]

🤖 Thank you for contributing to CiviCRM! ❤️ We will need to test and review this PR. 👷

Introduction for new contributors...

• If this is your first PR, an admin will greenlight automated testing with the command ok to test or add to whitelist.
• A series of tests will automatically run. You can see the results at the bottom of this page (if there are any problems, it will include a link to see what went wrong).
• A demo site will be built where anyone can try out a version of CiviCRM that includes your changes.
• If this process needs to be repeated, an admin will issue the command test this please to rerun tests and build a new demo site.
• Before this PR can be merged, it needs to be reviewed. Please keep in mind that reviewers are volunteers, and their response time can vary from a few hours to a few weeks depending on their availability and their knowledge of this particular part of CiviCRM.
• A great way to speed up this process is to "trade reviews" with someone - find an open PR that you feel able to review, and leave a comment like "I'm reviewing this now, could you please review mine?" (include a link to yours). You don't have to wait for a response to get started (and you don't have to stop at one!) the more you review, the faster this process goes for everyone 😄
• To ensure that you are credited properly in the final release notes, please add yourself to contributor-key.yml
• For more information about contributing, see CONTRIBUTING.md.

Quick links for reviewers...

• ➡️ PR Demo site (can be rebuilt with the command test this please).
• 📖 Review standards
• 🗒️ Review template (brief or verbose)

➡️ Online demo of this PR 🔗