Add expressive conditional gate support based on classical control

[grageragarces]

We want to support conditional quantum gates driven by measured classical control bits. The new cond_flag="p" interface in Circuit.add_instruction() starts this, but it needs to be extended to other models (notably MBQC corrections) and re-implemented in available converters as current mapping versions there are missing (qasm) or deprecated (qiskit).

[grageragarces]

Current Behavior

circuit.add_instruction("measure", [4])
circuit.add_instruction("z", [4], cond_flag="p")

Results in:

• A classical output node c4_tX from measure
• A predicted quantum node q4_tX+1
• A classical edge from c4_tX and q4_tX → q4_tX+1