Add pass: insert implicit record ops to entrypoint

[rainij]

Create a pass which takes IR similar to this:

// NOTE: important is that this has the `entrypoint` attribute (name does not matter).
func.func public @main() -> ... attributes { qcc.entry_point } {
  // ...
  return %a, %b : i64, i1
}

And replaces it by something like this (details can be carved out in PR):

func.func public @main() -> void attributes { qcc.entry_point } {
  // ...
  aux.record_integer %a : i64 // this op needs to be added
  aux.record_bool %b : i1     // this op already exists
  return
}

This follows the recipe of QIR output recording.

Note that QIR enables one to assemble complex data structures to be recorded. For example to record something like (1, 2, [true, false]) (tuple of two ints and an array of bools). This would need "tuple record" and "array record" ops / QIR-funcs in case we want to support it.

• Support for integers and bools.
• Support for arrays and tuple (recursively).

Motivation (Qrisp)

Consider the following qrisp (python) example

from qrisp import *
from qrisp.jasp import make_jaspr
import jax.numpy as jnp

def example():
    qv = QuantumVariable(2)
    h(qv[0])
    cx(qv[0], qv[1])
    a = measure(qv) + 5 # becomes i64 (more precisely: tensor<i64>)
    b = True            # becomes i1 (more precisely: tensor<i1>)

    # There are also things like this, but we leave them out in the first iteration as 
    # they get unpacked within the return statement (c, d, e become three times tensor<i64>
    # (each) which is impossible to distinguish from three integer variables).
    c = [1, 2, 3]
    d = (1, 2, 3)
    e = (1, [2, 3])

    return a, b #, c, d, e

jaspr = make_jaspr(example)()
mlir_stablehlo = jaspr.to_mlir()
print(mlir_stablehlo)

This gets translated into this mlir:

builtin.module @jasp_module {
  func.func public @main(%arg13: !jasp.QuantumState) -> (tensor<i64>, tensor<i1>, !jasp.QuantumState) {
    // create %10 etc here ...
    func.return %12, %13, %10 : tensor<i64>, tensor<i1>, !jasp.QuantumState
  }
...
}

After some lowering this will likely look as above. Note that @main is by convention the name of the entrypoint of a qrisp program. There will be a pass which adds the corresponding attribute.