[C] Command Sample

[vaavva]

Purpose

• Adds Command Sample for C
  • Uses MQTT 5
    • Uses Correlation ID (validates against the last correlation ID sent)
    • Uses Response Topic
    • Uses Content Type (to match C# sample)
  • Sends unlock command every 2 seconds if it's received a response (request times out after 10 seconds otherwise)
  • Command Client sends the command request to the Command Server, which sends back a command response
• Does NOT support protobuf in this PR (payload is currently mocked to work with C# sample)
• Currently target vehicle name for the request/response topic is hard-coded until we establish a pattern of setting it

Checklist

• [x] I have read the contribution guidelines.
• I submitted this PR against the correct branch:
  • [x] This pull-request is submitted against the main branch.
  • [x] I have merged the latest main branch prior to submission and re-merged as needed after I took any feedback.
  • [x] I will squashed my changes into one with a clear description of the change when I complete the PR.

Does this introduce a breaking change?

[ ] Yes
[x] No

Pull Request Type

What kind of change does this Pull Request introduce?

[ ] Bugfix
[x] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

How to Test

• Follow Readme instructions (https://github.com/Azure-Samples/MqttApplicationSamples/blob/vaavva/c-command/scenarios/command/README.md#c)

What to Check

Verify that the following are valid

• Works with Server/Client running C Samples
• Works with C Server/C# Client
• Works with C# Server/C Client

Other Information