add deprecation marks

[DanielMSchmidt]

This PR prepares deprecations as a concept in TF. For the full end-to-end implementation see #37795, this PR splits up that work into more reviewable chunks.

Fixes #

Target Release

1.15.x

Rollback Plan

• If a change needs to be reverted, we will roll out an update to the code within 7 days.

Changes to Security Controls

Are there any changes to security controls (access controls, encryption, logging) in this pull request? If so, explain.

CHANGELOG entry

• This change is user-facing and I added a changelog entry.
• This change is not user-facing.

[jbardin]

Should we try tracking some source address and attribute path info here, maybe something like a globalref.Reference? While we can render the source position once the diagnostic is printed, that doesn't directly tell the user which type and attribute path is being used.

[DanielMSchmidt]

Currently the origin is sort of unused, we just show the expression containing the mark where it is used. I wanted to do a bit more work towards a good error message that show both where it's used and the origin, but that is more aspirational. I could remove origin for now while it's unused?

[jbardin]

Yeah, maybe we leave it out for now, rather than have a half-solution. Maybe because we render these at the first point of usage, there's enough context for users to know where the problematic source is?

[DanielMSchmidt]

I would think so. I definitely want to do a spike on a nice "this is the usage and this over here is the origin of the mark" diagnostic message but I haven't had the time and energy to delve into that yet 😅

[dsa0x]

Is there any reason for this to be a public API? If it is only used internally to type-check, then maybe not

[DanielMSchmidt]

It has to be, so that you can do e.g. marks.Has(value, marks.Deprecation)