Draft: Support mamba layer fine grained offloading with cudagraphs

[jiemingz]

What does this PR do ?

Support offloading to mamba input and output projections, and support cudagraphing them. There will be a followup PR to add a unit test, which will be part of a larger refactor of the cudagraph unit tests.

⚠️ For major changes (either in lines of code or in its impact), please make sure to first share a design doc with the team. If you're unsure what's the best way to do so, contact the @mcore-oncall.

Contribution process

flowchart LR
    A[Pre-checks] --> B[PR Tests]
    subgraph Code Review/Approval
        C1[Expert Review] --> C2[Final Review]
    end
    B --> C1
    C2 --> D[Merge]

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Pre-checks

• I want this PR in a versioned release and have added the appropriate Milestone (e.g., Core 0.8)
• I have added relevant unit tests
• I have added relevant functional tests
• I have added proper typing to my code Typing guidelines
• I have added relevant documentation
• I have run the autoformatter.sh on my PR

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[dimapihtar]

/ok to test 4fd8b86

[jiemingz]

/ok to test c437085

[jiemingz]

/ok to test 494e675