add Kestra flow schema

[benpops89]

Adds schema for Kestra flows.

Kestra is an orchestration framework similar to Airflow that defines it's pipelines (flows) in YAML. This schma provides auto-complete and validation of YAML.

When validating the schema I did get the following error Error: strict more: unknown keyword: "markdownDescription". It might be something specific to Kestra but not sure how it should be handled.

Solves #3978

[github-actions]

Thanks for the PR!

This section of the codebase is owned by @madskristensen and @hyperupcall - if they write a comment saying "LGTM" then it will be merged.

[hyperupcall]

Hey, thanks for this PR

When validating the schema I did get the following error Error: strict more: unknown keyword: "markdownDescription". > It might be something specific to Kestra but not sure how it should be handled.

Schemas are validated with Ajv, which has a "strict mode" that we enable to catch common issues. More information is in the documentation, but you can edit src/schema-validation.jsonc, and add your unknown key name to the "options[$schemaName].unknownKeywords" field. If you would like to disable strict mode checks all together, you can edit the "ajvNotStrictMode" top-level field.

[benpops89]

@hyperupcall - thanks for pointing me in the right direction. I have added a list of unknownKeywords for Kestra to that file and the checks are passing.

[hyperupcall]

@benpops89 Thanks - there appears to be one more failure in CI - spellcheck. The list of ignored words can be changed in .pre-commit-config.yaml if you need to update that;

[benpops89]

@hyperupcall - thanks for your support on this. I have run codespell locally and fixed all the typos in the file and added one word CopyIn to the list of ignored words and the tests are now passing 🚀

[hyperupcall]

Awesome, thank you!