[MoE][Refactor] Remove most arguments to FusedMoEMethodBase.apply

[bnellnm]

Purpose

After making select_experts a non-static method (#29067), we can avoid passing most of the arguments to FusedMoEMethodBase.apply and get them from the layer directly.

This doesn't really decrease flexibility, the MoE quantization methods were already fairly tightly coupled with FusedMoE. A further step could be making FusedMoE an abstract base class that simply provides the quant_method parameters. Then the current FusedMoE class would become a subclass of that.

Test Plan

CI

Test Result

Blackwell failure is known bug fixed by #30336

cc @varun-sundar-rabindranath

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[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @bnellnm.

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[LucasWilkinson]

Looks like we need to land #29067 first? marking draft until that lands 👍

[bnellnm]

• draft

Yeah, sorry this should have been a draft to start with. It needs the other PR to land first.

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @bnellnm.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[mergify]

Hi @bnellnm, the pre-commit checks have failed. Please run:

uv pip install pre-commit
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pre-commit run --all-files

Then, commit the changes and push to your branch.

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# For mypy (substitute "3.10" with the failing version if needed)
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[mergify]

Hi @bnellnm, the pre-commit checks have failed. Please run:

uv pip install pre-commit
pre-commit install
pre-commit run --all-files

Then, commit the changes and push to your branch.

For future commits, pre-commit will run automatically on changed files before each commit.

Tip

Is mypy or markdownlint failing?

mypy and markdownlint are run differently in CI. If the failure is related to either of these checks, please use the following commands to run them locally:

# For mypy (substitute "3.10" with the failing version if needed)
pre-commit run --hook-stage manual mypy-3.10
# For markdownlint
pre-commit run --hook-stage manual markdownlint

[mgoin]

Great work Bill! Thinking now on the state, the main downside I see of this move is that since we aren't passing arguments into the function, it is less explicit for each apply method to assert against unsupported modes as we add more. Hopefully we can move to a system like the attention backends for each kernel backend