Use a -1 non-broadcastable constraint encoding for static shapes

[brandonwillard]

This PR investigates the use of a -1 static shape value encoding to indicate that a dimension's shape value is not equal to one (per #1122).

Integers s are used to encode static shape constraints as follows:

• s <= -2: the least amount of shape information (currently None)
• s == -1: the shape is not equal to one
• -1 < s: the most amount of shape information (i.e. the shape is strictly equal to s)

In its current form, this PR adds a TensorType.shape_encoded attribute and converts the old TensorType.shape into a computed property that simply converts the non-exact constraints (i.e. s < 0) to None.

• Finish removing old uses of TensorType.broadcastable (especially when used as TensorType constructor arguments)
  The broadcastable argument to the TensorType constructor was removed and strict non-bool type checks were added in order to find all the places where True/False values are being used as shape values. This means that a lot of the tests will fail until those are all fixed.
  Basically, this PR is also serving as an investigation into all the logic that still relies on TensorType.broadcastable.
• More direct tests of the new constraint
• Propagate the new constraint in as many cases as possible/reasonable
• Rebase on top of Replace some uses of TensorType.broadcastable with TensorType.shape #1297

[codecov]

Codecov Report

Merging #1280 (6454f54) into main (9ec71c8) will decrease coverage by 0.01%.
The diff coverage is 82.85%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1280      +/-   ##
==========================================
- Coverage   74.22%   74.21%   -0.02%     
==========================================
  Files         174      174              
  Lines       48731    48765      +34     
  Branches    10367    10381      +14     
==========================================
+ Hits        36170    36189      +19     
- Misses      10273    10285      +12     
- Partials     2288     2291       +3     

Impacted Files	Coverage Δ
aesara/link/jax/dispatch/shape.py	78.04% <0.00%> (-8.44%)	⬇️
aesara/tensor/type.py	89.34% <86.48%> (-1.61%)	⬇️
aesara/tensor/shape.py	91.42% <92.30%> (-0.31%)	⬇️
aesara/link/numba/dispatch/basic.py	92.69% <100.00%> (+0.01%)	⬆️