Add bind_nested_plxpr meta-transform

[albi3ro]

HIGHLY EXPERIMENTAL

Context:

This is part of an ongoing project to improve the ability to capture pennylane code into a hybrid intermediate representation.

Description of the Change:

This PR adds a qml.capture.bind_nested_plxpr meta-transform that automatically integrates qfunc transforms with
PLXPR. It:

• Creates the associated primitive
• Defines concrete and abstract implementations for the primitive
• Hijacks calling the quantum function to instead create jaxpr and bind it to the primitive

Benefits:

Easy binding of qfunc transforms into PLXPR via a straightforward decorator/ meta-transform.

Possible Drawbacks:

The handling of keyword arguments is a bit shaky.

This level of nesting in function definitions can be really hard to read.

When I was messing around with it, I think I saw a memory leak, and not sure if its still there or not.

Related GitHub Issues:

[sc-59448]

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[trbromley]

@albi3ro what is the status of this PR, do we still need it?