feat: support generic funcs

[txabman42]

Contributing to #169

More info in ☝️ issue about why Hooks use interface{} as argument type:

func GenericExample[K comparable, V any](value T) map[K]V { ... }

func GenericHookBefore(ictx inst.HookContext, k interface{}, v interface{}) { ... }

func GenericHookAfter(ictx inst.HookContext, r interface{}) { ... }

This PR also add the support for parameter grouping in hooks, example:

func MyHookGenericBefore(ictx inst.HookContext, _, _ interface{}) { ... }

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What to Expect for the Reviews

[pdelewski]

Good Job!

[y1yang0]

Thanks for your contribution!

I didn't expect the implementation to be this clean and elegant

[y1yang0]

Add test case func (recv *Recv[T]) GenericExample

[txabman42]

Test added.

There were some extra changes needed to support this case:

• Extract receiver type parameters
• Set hook ctx params as a combination of receiver and function types
• Preserve generics in trampolines

This new code would require some new 👀 63a9420

[y1yang0]

The SetParam/SetReturnVal function is intended to modify the parameters of the original function, but the current implementation doesn't allow this. We should rewrite it to panic (or something similar) to reject user calls and make it clear this operation is unsupported.

[txabman42]

This would require a extra bit of code. Do you see any direct approach?

WDYT about moving this to a new issue? This PR is starting to get big

[y1yang0]

The documentation needs to be updated to state that SetParam and SetReturnVal cannot be used with generic hook functions.

[txabman42]

We can document these limitations as part of #194. They should be more related to hooks than rules itself.

[y1yang0]

rectifyAnyType() already does this. Why do we need to repeat it here?

[txabman42]

They are not exactly the same.

For example:
func (t *T) Func1(p1 string, p2 int)

The receiver trait is marked as IsInterfaceAny and replaced here, so it ends up in:

func H3Before(ctx inst.HookContext, recv interface{}, p1 string, p2 int)

TestInstrumentation_Integration/method-receiver covers this case.

However, it could be simplified 58aa8e3