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Handle custom operations with overlapping names in QPY (#11646)

* Handle custom operations with overlapping names in QPY

This commit fixes a longstanding bug and limitation in QPY around the
use of custom operations. When QPY encounters a non-standard (meaning not
in Qiskit itself, or a direct instance of Gate or Instruction)
instruction it is not able to represent the exact instance perfectly in
that payload. This is because it would require more code that represents
those classes or data not contained inside Qiskit itself, which would be
an opportunity for arbitrary code execution which is something QPY was
designed to prevent (as it's a limitation with pickle serialization). So
to serialize these objects in a circuit, QPY stores as much data as it
can extract from the data model from the Instruction and Gate classes
and builds a table of custom instructions that will be recreated as
Instruction or Gate instances on deserialization. In all previous QPY
format versions that table was keyed on the .name attribute of the
custom instructions in the circuit, the thinking being the name is a
unique op code during circuit compilation and if there are multiple
circuit elements with the same name they should be the same object. With
this assumption it enabled the QPY payloads generated with repeated
custom instructions to be smaller and more efficient because we don't
need to store potentially repeated data. While that assumption is true
during most of compilation it was ignoring that for a bare quantum
circuit (or during the initial stages of compilation) this isn't
necessarily true and there are compiler passes that canonicalize custom
operations prior to that being true. To make it worse this assumption
was causing conflicts in the QPY payload and cause an inaccurate
reproduction of the original circuit when deserializing a QPY payload in
many cases when custom gates were used.

This commit fixes this limitation by introducing a new QPY format
version 1... (continued)

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Source Files on job 7728099338.1