Feature: Support of Manifold Hyper Connection(mHC)

[jingqiny-99]

What does this PR do ?

mirror PR of #2943

⚠️ 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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For MRs into `main` branch

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[jingqiny-99]

/claude review

[jingqiny-99]

/ok to test 6a1e311

[jingqiny-99]

/ok to test 35b1bec

[jingqiny-99]

/ok to test 9b1e544

[jingqiny-99]

/ok to test 3431dab

[Phlip79]

Should this PR remain open given #3828?

[FDecaYed]

Should this PR remain open given #3828?

#3828 was a follow up optimization on top of original PR. since it is kernel only and self contained, @jingqiny-99 has since merged it together into this PR for main. It is final and ready for review now

[Phlip79]

@jingqiny-99 this PR is quite large and I think would benefit from being split into multiple smaller PRs. A new Claude skill /split-pr has been introduced to make this process easier for authors. Can you please give it a try?

[jingqiny-99]

@jingqiny-99 this PR is quite large and I think would benefit from being split into multiple smaller PRs. A new Claude skill /split-pr has been introduced to make this process easier for authors. Can you please give it a try?

Sure, I'll try it.