docs: Add some example notebooks for the python package.

[aborgna-q]

The code in the notebooks requires #442, #441, and #444

Closes #434

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.05%. Comparing base (525b63f) to head (30f61db).
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@@             Coverage Diff             @@
##             main     #443       +/-   ##
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+ Coverage   80.93%   97.05%   +16.11%     
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  Files          60       17       -43     
  Lines        5896      509     -5387     
  Branches     5387        0     -5387     
===========================================
- Hits         4772      494     -4278     
+ Misses        881       15      -866     
+ Partials      243        0      -243     

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[ss2165]

• guppy is about to stop returning results and use a result function. How breaking will this be? feat: Add result function guppylang#271
• the no_type_checks and pragma: no_covers are adding annoying noise. Find a way around python type checkers complaining about guppy guppylang#277
• define guppy_to_circuit in a separate file? jupyter notebooks can do local imports
• for zzphase(0.5) -> cnot the text says "replaced with just cx and rz" but the actual rhs has way more Rzs going on?
• is the pauli propagation copying the one in the tests?

[aborgna-q]

• guppy is about to stop returning results and use a result function. How breaking will this be? feat: Add result function guppylang#271

We'll just ignore Result operations. I'll have to think about how to encode them into pytket circuits, but for tket2 circuits we only care about the function definitions with explicit outputs. Result should be akin to a print statement we'll optimise around.

• the no_type_checks and pragma: no_covers are adding annoying noise. Automatically annotate guppy definitions with @no_type_check guppylang#277

As Mark mentioned there, they cannot be added programmatically u.u
But we do not check notebook code, so maybe I should remove them here.

• define guppy_to_circuit in a separate file? jupyter notebooks can do local imports

Will do 👍

• for zzphase(0.5) -> cnot the text says "replaced with just cx and rz" but the actual rhs has way more Rzs going on?

I'll fix the text

• is the pauli propagation copying the one in the tests?

Yes, it's an extract of your code. That works well as an example of how to use the pattern matcher for more complex operations, so it seemed like a good thing to include here.
It some point we may want to expand it on its own notebook, but here we just have a quick overview of all the features.

[ss2165]