🎨 ♻️ Restructure code around the actor model

[linkdd]

Decision Record

We used the go-actor library to structure part of the code.
Here, we restructure the entire codebase to make use of it everywhere, thus simplifying the wworkflow, error reporting, dependencies, etc...

A few bugs were uncovered during this refactor:

• every time we needed to execute a transformer, we had to read it from the filesystem
• the configuration storage was subject to race conditions (the file system is not thread safe)
• some API operations were checking the wrong permissions

Changes

• 🎨 Refactor code to use more of the actor model
• ⚡ use sync.Map in the configuration storage as a cache to speed up reads and avoid race conditions
• 🐛 fix permission checking in API

License Agreement

• I guarantee that I have the rights on the code submitted in this PR
• I accept that this contribution will be released under the terms of the MIT License

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
3.3% Duplication on New Code

See analysis details on SonarCloud

[github-actions]

	Tests	Passed ✅	Skipped ⏭️	Failed ❌
End-To-End Test Report	11 ran	11 passed	0 skipped	0 failed