Remove support for `--format yaml`

[cmaglie]

Describe the request

Remove support for output format yaml in the --format flag.

Rationale:

• Support for YAML is not implemented in all commands, particularly commands with streaming output, or is poorly maintained/tested compared to the JSON output.
• it complicates the code without any worthwhile benefit (especially outputting YAML requires specific struct-tagging or special libraries like sigs.k8s.io/yaml)

Describe the current behavior

N/A

Arduino CLI version

nightly

Operating system

N/A

Operating system version

N/A

Additional context

The original PR that introduced the feature is this one: #1600 but it seems that the requested feature was for another project using the feedback package as a library. This is no longer possible with the latest version of the Arduino CLI.

Issue checklist

• I searched for previous requests in the issue tracker
• I verified the feature was still missing when using the nightly build
• My request contains all necessary details

[aliphys]

.yml files can be included alongside the sketch, which will act as sketch build profiles. This stores the platform and library versions in use, as described in https://arduino.github.io/arduino-cli/0.36/sketch-project-file/

• Will this proposal deprecate the use of .yml files in this way? See this PR for example implementation involving the Arduino_UnifiedStorage library
• If yes, then is there an alternative/recommended route to defining the sketch project file without .yml? Maybe with json instead?

Thanks!

[cmaglie]

Will this proposal deprecate the use of .yml files in this way?

No, sketch project files sketch.yml or configuration file arduino-cli.yaml will continue to work as always. This change request is relative ONLY to the --format yaml flag.