tracking issue: Lower guppy-generated `Circuit`s into `pytket`

[aborgna-q]

Given a tket2.Circuit generated from a guppy definition (see #303), rewrite into something that can be translated into a tket_json_rs::SerialCircuit.

The following tasks are the bare minimum to support a restricted subset of guppy programs:

• [x] #380
  • This may be a Hugr-side pass
• [x] #407
• [x] #379
  • Translate the measurements and classically controlled operations.
• [x] #389
• [x] #418

Extended tket1 support:

• [ ] Translate classically controlled operations into tket2 (and back)
• [ ] https://github.com/CQCL/tket2/issues/44
• [ ] Translate tk1 logical expressions
• [ ] #428
• [ ] Support n-qubit controlled operations

Extended hugr support:

• [ ] https://github.com/CQCL/hugr/issues/818
• [ ] Flatten TailLoops
• [ ] Flatten Conditionals
• [ ] Inline function calls

[aborgna-q]

Closing this as completed since the core tasks are done. I opened two new tracking issues for the other categories