chore: chain/actors: Use type proxies instead of versioned GST imports

[magik6k]

Related Issues

Started doing as part of #11125 when weaving through the new nv21 DDO types through the Piece/Sector sealing pipeline, but the rabbit hole turned into a small cave system

Proposed Changes

• Use type aliases in chain/actors/builtin instead of importing versioned go-state-types structs all over the place
• This in principle should allow us to easily switch from importing v9 types everywhere to higher versions much more easily
• But not quite yet with just this PR, though it gets us much closer to less pain

Additional Info

There should be zero logic changes as the effect of this PR, just swapping how we import/use actor types in the codebase.

Checklist

Before you mark the PR ready for review, please make sure that:

• Commits have a clear commit message.
• PR title is in the form of of <PR type>: <area>: <change being made>
  • example: fix: mempool: Introduce a cache for valid signatures
  • PR type: fix, feat, build, chore, ci, docs, perf, refactor, revert, style, test
  • area, e.g. api, chain, state, market, mempool, multisig, networking, paych, proving, sealing, wallet, deps
• New features have usage guidelines and / or documentation updates in
  • Lotus Documentation
  • Discussion Tutorials
• Tests exist for new functionality or change in behavior
• CI is green