[MNT] compatibility with scipy>=1.14.0 and python 3.13

[ouslan]

Replaces some long deprecated function calls to ensure compatibility with higher scipy and python versions.

• Change .A to .toarray() in pygam/pygam.py
• Change .A to .toarray() in pygam/terms.py
• Change .A to .toarray() in pygam/tests/test_terms.py
• Change .A to .toarray() in pygam/utils.py
• Change .A to .toarray() and np.alltrue() to np.all()pygam/tests/test_penalties.py`

Also added environment directory to .gitignore

[dswah]

cool!

[fkiraly]

shall we try with the new CI matrix before merging?

[codecov]

Codecov Report

Attention: Patch coverage is 94.73684% with 1 line in your changes missing coverage. Please review.

Project coverage is 95.00%. Comparing base (a6c14e4) to head (9ab74b0).
Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
pygam/utils.py	75.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #366   +/-   ##
=======================================
  Coverage   95.00%   95.00%           
=======================================
  Files          22       22           
  Lines        3202     3202           
=======================================
  Hits         3042     3042           
  Misses        160      160           

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[fkiraly]

i.e., merging this first: #383