[PoC] Use cog to generate go and typescript models + resources

[K-Phoen]

Draft PR meant to try out cog as a potential replacement for Go and Typescript codegen purposes.

ToDo:

• the thema.CustomKindParser provided by grafana-app-sdk used with cog's CUE parser struggle to correctly handle references to objects defined "above" the currently parsed root. Ex:

  #InnerObject2: { // ← object defined "above" the current root
      name: string
      details: {
          [string]: _
      }
  }
  
  spec: { // ← current root
      inner: #InnerObject1
      // ...
  }

  Cog detects this case correctly, gets the path to InnerObject2 (something like customKind.lineage._sortedSchemas[1]._#schema.#InnerObject2), but resolving this path (with LookupPath() fails on hidden fields introduced by thema (_sortedSchemas and _#schema).
  If thema support isn't meant to stick around long-term, this issue might not be worth solving.

Note: this PR isn't necessarily meant to be finished or merged, it's more a sandbox to play with cog + grafana-app-sdk.

[radiohead]

@K-Phoen thank you for experimenting with this! This is something that's been on our radar for a while, but we never had any bandwidth for.

Please let us know if we can help get this ready for a review. One notable change we've made since this PR was opened is that we got rid of Thema support, so this should no longer be an issue.

[K-Phoen]

Not having to support Thema schemas should simplify things :)

I'll get back to working on this and let you know if I need a hand!

[K-Phoen]

Closing this in favor of #485