Create generic tedge configuration plugin

[Ruadhri17]

Proposed changes

This PR adds generic configuration plugin
TODO:

• Replace device-topic-root and device-topic-identifier with the one from tedge config
• Add downloader actor for config update

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Improvement (general improvements like code refactoring that doesn't explicitly fix a bug or add any new functionality)
• Documentation Update (if none of the other choices apply)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Paste Link to the issue

• Make configuration plugin usable for different clouds #2098
• Move cloud specific logic out of plugins #2017

Checklist

• I have read the CONTRIBUTING doc
• I have signed the CLA (in all commits with git commit -s)
• I ran cargo fmt as mentioned in CODING_GUIDELINES
• I used cargo clippy as mentioned in CODING_GUIDELINES
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

Further comments

[github-actions]

Robot Results

✅ Passed	❌ Failed	⏭️ Skipped	Total	Pass %	⏱️ Duration
288	0	3	288	100	1h0m33.033999999s

[rina23q]

Since it's still draft, I didn't dive into details, but Cargo.toml you can fix quickly.

[codecov]

Codecov Report

Merging #2238 (f75f5c2) into main (be351da) will decrease coverage by 0.2%.
The diff coverage is 72.3%.

Additional details and impacted files

Files Changed	Coverage Δ
crates/core/tedge_api/src/mqtt_topics.rs	80.6% <0.0%> (-1.3%)	⬇️
...rates/extensions/tedge_config_manager/src/error.rs	0.0% <0.0%> (ø)
plugins/tedge_configuration_plugin/src/main.rs	0.0% <0.0%> (ø)
...ates/extensions/tedge_config_manager/src/config.rs	59.8% <59.8%> (ø)
...rates/extensions/tedge_config_manager/src/actor.rs	69.4% <69.4%> (ø)
crates/core/tedge_api/src/messages.rs	92.1% <78.5%> (-0.8%)	⬇️
crates/extensions/tedge_config_manager/src/lib.rs	91.4% <91.4%> (ø)
...rates/extensions/tedge_config_manager/src/tests.rs	91.9% <91.9%> (ø)

... and 7 files with indirect coverage changes

[rina23q]

I'm still not finishing review, but I would submit now and will continue review tomorrow.

My general questions is:

• Do we need to create a library crate to avoid the code duplication between c8y-configuration-manager and tedge-configuration-manager?

I would also remark that this implementation omits timer_actor, which exists in c8y-configuration-manager. Need to think which one is appropriate one to address the timeout, mapper or plugin?

[didier-wenzek]

Approved

[rina23q]

I tested according to the spec. It works, and addressing error cases! Very good job!

Almost all of my comments are minor. The exception is the default contents of the tedge-configuration-plugin.toml file, but it should be one-liner change, so you only need 1 minute to fix it.
For others, If you have time, you can modify them. But don't spend too much time. If you feel it's too much change, then stop and we can merge this PR.

[rina23q]

LGTM!