feat: create globalConfig from app.manifest

[hetangmodi-crest]

Issue number: ADDON-78488

PR Type

What kind of change does this PR introduce?

• Feature
• Bug Fix
• Refactoring (no functional or API changes)
• Documentation Update
• Maintenance (dependency updates, CI, etc.)

Summary

Changes

Going forward, if the globalConfig doesn't exist in the source directory of an add-on, the UCC framework would create one in the source directory and then proceed with processing of the build process.

User experience

Users using UCC framework for .conf-only TAs would now see a globalConfig.json created in their source code / source directory when they run the ucc-gen build --source ... command.

Checklist

If an item doesn't apply to your changes, leave it unchecked.

Review

• self-review - I have performed a self-review of this change according to the development guidelines
• Changes are documented. The documentation is understandable, examples work (more info)
• PR title and description follows the contributing principles
• meeting - I have scheduled a meeting or recorded a demo to explain these changes (if there is a video, put a link below and in the ticket)

Tests

See the testing doc.

• Unit - tests have been added/modified to cover the changes
• Smoke - tests have been added/modified to cover the changes
• UI - tests have been added/modified to cover the changes
• coverage - I have checked the code coverage of my changes (see more)

Demo/meeting:

Reviewers are encouraged to request meetings or demos if any part of the change is unclear

[artemrys]

Comment for other folks reviewing - the diff is much better if you use "Unified" diff view and hide whitespaces.

[github-actions]

Code Coverage 🎉

Type	PR	Develop	Change	Status
Line Coverage	87.09%	86.94%	0.15%	🟢 Increased
Branch Coverage	80.34%	80.19%	0.15%	🟢 Increased