Fix send_event() in c8y_http_proxy to create events under child devices

[rina23q]

Proposed changes

c8y-mapper should create an event for a child device via HTTP when the event size exceeds the MQTT threshold. However, it was created for the main device instead. This PR fixes the issue.

The root cause how to get the device_id (= c8y's internal device ID) in this part of the code.

thin-edge.io/crates/extensions/c8y_http_proxy/src/actor.rs

Lines 310 to 314 in 9dea122

	// If the incoming event does not have any source mentioned explicitly,
	// it is associated to the main device by default.
	let device_id = c8y_event
	.source
	.map_or_else(|| self.end_point.device_id.clone(), |v| v.id);

c8y_event.source needs to hold an internal ID, however, it's too early to expect to have an internal ID as source. If we have to use the current implementation, one has to get the device's internal ID in the mapper's converter level (= the c8y_event object in the the below code has to have its internal ID as source). Querying an internal ID should be definitely hidden inside c8y_http_proxy API.

thin-edge.io/crates/extensions/c8y_mapper_ext/src/converter.rs

Line 468 in 9dea122

let _ = self.http_proxy.send_event(c8y_event).await?;

For this reason, I introduced a new struct CreateEvent to parse device's external ID to c8y_http_proxy API.

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

#2394

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
357	0	3	357	100	1h1m8.257999999s

[codecov]

Codecov Report

Merging #2421 (300c14b) into main (9dea122) will increase coverage by 0.0%.
Report is 12 commits behind head on main.
The diff coverage is 82.9%.

Additional details and impacted files

Files	Coverage Δ
crates/extensions/c8y_http_proxy/src/handle.rs	73.3% <100.0%> (ø)
crates/extensions/c8y_http_proxy/src/tests.rs	91.7% <100.0%> (-0.1%)	⬇️
crates/extensions/c8y_http_proxy/src/actor.rs	49.4% <75.0%> (-0.5%)	⬇️
crates/extensions/c8y_http_proxy/src/messages.rs	26.6% <0.0%> (-2.0%)	⬇️
crates/extensions/c8y_mapper_ext/src/converter.rs	81.0% <83.8%> (+0.6%)	⬆️

... and 6 files with indirect coverage changes

[albinsuresh]

LGTM