Feat/add app metadata controller

[frankvonhoven]

Explanation

Porting over the AppMetadataController from Extension

References

Changelog

@metamask/app-metadata-controller

• : Adds new metadata controller

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've highlighted breaking changes using the "BREAKING" category above as appropriate
• I've prepared draft pull requests for clients and consumer packages to resolve any breaking changes

[mikesposito]

I see that this controller has no public method, how do we intend the client to interact with this package?
I just realized that the extension is already using the package via the constructor alone, which I feel is a little weird, but I guess goes beyond the scope of this PR

[mikesposito]

Could we add a root src/index.ts that exports the relevant objects?
i.e.

// src/index.ts
export * from './AppMetadataController`

[mikesposito]

We should also add these changes to configuration files:

• .github/CODEOWNERS for assigning the relevant owners to this package
• tsconfig.json and tsconfig.build.json for adding the package to the workspace

Also, README should also be updated by running yarn update-readme-content

[mcmire]

Left some comments!

[mcmire]

It looks like lint is failing. I provided some suggestions on how to fix it.

If you need to run lint for just these files again, try

yarn eslint packages/app-metadata-controller

[mcmire]

One more thing and then I think we're good.

[mcmire]

Looks good! 🎉