feat: JointEmbeddingSCVI

[ori-kron-wis]

added files from Valentine's repo

[codecov]

Codecov Report

❌ Patch coverage is 91.81034% with 19 lines in your changes missing coverage. Please review.
✅ Project coverage is 88.56%. Comparing base (5dacc67) to head (b209068).

Files with missing lines	Patch %	Lines
.../low_count_models/deterministic_thinned/_module.py	66.66%	13 Missing ⚠️
.../scvi/external/low_count_models/thinned/_module.py	82.60%	4 Missing ⚠️
...scvi/external/low_count_models/non_zero/_module.py	97.14%	1 Missing ⚠️
...l/low_count_models/utils/_joint_embedding_utils.py	96.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3748      +/-   ##
==========================================
+ Coverage   88.53%   88.56%   +0.03%     
==========================================
  Files         237      252      +15     
  Lines       23827    24059     +232     
==========================================
+ Hits        21095    21309     +214     
- Misses       2732     2750      +18     

Flag	Coverage Δ
integration	72.79% <91.81%> (+0.18%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
src/scvi/external/__init__.py	86.11% <100.00%> (+0.39%)	⬆️
src/scvi/external/low_count_models/__init__.py	100.00% <100.00%> (ø)
...low_count_models/deterministic_thinned/__init__.py	100.00% <100.00%> (ø)
...l/low_count_models/deterministic_thinned/_model.py	100.00% <100.00%> (ø)
...ernal/low_count_models/joint_embedding/__init__.py	100.00% <100.00%> (ø)
...xternal/low_count_models/joint_embedding/_model.py	100.00% <100.00%> (ø)
...ternal/low_count_models/joint_embedding/_module.py	100.00% <100.00%> (ø)
...cvi/external/low_count_models/non_zero/__init__.py	100.00% <100.00%> (ø)
.../scvi/external/low_count_models/non_zero/_model.py	100.00% <100.00%> (ø)
...scvi/external/low_count_models/thinned/__init__.py	100.00% <100.00%> (ø)
... and 6 more

... and 2 files with indirect coverage changes

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[ori-kron-wis]

close #3734

[ori-kron-wis]

copy of #3884