refactor!: Change bool lowering to an opaque type

[tatiana-s]

Closes #862

BREAKING CHANGE: Bools in HUGRs generated by Guppy are represented using a tket2.bool instead of the HUGR sum type

[tatiana-s]

(draft because this depends on both a tket2 release and also for the lowering to Sum( Sum( () | () ), ResultId) in hugr)

[tatiana-s]

main things I am unsure about is where to put all the bool definitions (currently in tket2_bool.py in the std compiler), and also I was surprised I didn't seem to have to change anything with tail loops to make all the tests pass

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 99.29078% with 1 line in your changes missing coverage. Please review.

Project coverage is 92.78%. Comparing base (498f3fb) to head (9e7a836).

Files with missing lines	Patch %	Lines
guppylang/std/_internal/compiler/tket2_bool.py	95.83%	1 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #900      +/-   ##
==========================================
- Coverage   92.89%   92.78%   -0.11%     
==========================================
  Files          83       85       +2     
  Lines        9797     9887      +90     
==========================================
+ Hits         9101     9174      +73     
- Misses        696      713      +17     

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