[ESI] BSP: variable sized reads and gearboxing read responses

[teqdruid]

Adds the ability to have hostmem read clients issue reads for types which are not 64-bit. Requires changes to the cosimulated hostmem to properly respond with multiple messages when necessary. Also requires a tag-sensitive gearbox to re-assemble data which requires more than one message from upstream.

Copilot reviewed 5 out of 9 changed files in this pull request and generated no comments.

Files not reviewed (4)

• lib/Dialect/ESI/runtime/cpp/lib/backends/Cosim.cpp: Language not supported
• lib/Dialect/ESI/runtime/cpp/tools/esitester.cpp: Language not supported
• frontends/PyCDE/integration_test/esitester.py: Evaluated as low risk
• frontends/PyCDE/src/pycde/bsp/common.py: Evaluated as low risk

Comments suppressed due to low confidence (2)

frontends/PyCDE/test/test_esi.py:4

• The import statement for 'unittest' is missing. This could cause issues with running the tests if they rely on 'unittest'. Add 'import unittest' at the beginning of the file.

from pycde import (Clock, Input, InputChannel, Output, OutputChannel, Module, Reset, generator, types)

frontends/PyCDE/src/pycde/constructs.py:266

• Ensure that the new 'clear' input functionality in the Counter module is covered by tests.

clear = Input(Bits(1))