refactor: Refactor Differentiability

[aturker-synnada]

Description

Closes #184.

What is Changed

Include the changes introduced in this PR.

• Differentiability flag now in Tensor.
• PM infer_differentiability logic is changed.

Checklist:

• Tests that cover the code added.
• Corresponding changes documented.
• All tests passed.
• The code linted and styled (pre-commit run --all-files has passed).

[codecov]

Codecov Report

Attention: Patch coverage is 95.83333% with 4 lines in your changes missing coverage. Please review.

Project coverage is 88.97%. Comparing base (8fb0a5d) to head (bb092a9).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
mithril/framework/common.py	93.54%	2 Missing ⚠️
mithril/framework/logical/base.py	87.50%	2 Missing ⚠️

@@            Coverage Diff             @@
##             main     #185      +/-   ##
==========================================
+ Coverage   88.96%   88.97%   +0.01%     
==========================================
  Files          62       62              
  Lines       16297    16311      +14     
==========================================
+ Hits        14498    14513      +15     
+ Misses       1799     1798       -1     

Files with missing lines	Coverage Δ
mithril/framework/logical/model.py	94.08% <100.00%> (+0.04%)	⬆️
mithril/framework/logical/operator.py	96.96% <100.00%> (+0.09%)	⬆️
mithril/framework/logical/operators.py	100.00% <100.00%> (ø)
mithril/framework/logical/primitive.py	100.00% <100.00%> (ø)
mithril/framework/physical/model.py	91.60% <100.00%> (-0.03%)	⬇️
mithril/models/models.py	90.06% <100.00%> (-0.03%)	⬇️
mithril/models/primitives.py	98.00% <ø> (-0.01%)	⬇️
mithril/models/train_model.py	91.97% <100.00%> (+0.02%)	⬆️
mithril/utils/dict_conversions.py	81.42% <100.00%> (ø)
mithril/framework/common.py	97.01% <93.54%> (-0.03%)	⬇️
... and 1 more

... and 2 files with indirect coverage changes

[kberat-synnada]

Issue explanation (#184) is not clear