Rag chunking embedding

[claudevdm]

Add rag types, chunking and huggingface embeddings.

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[claudevdm]

R: @damccorm

[github-actions]

Stopping reviewer notifications for this pull request: review requested by someone other than the bot, ceding control. If you'd like to restart, comment assign set of reviewers

[damccorm]

Left a few comments, but mostly they are minor - thanks!

[damccorm]

Minor (but useful) note - when you force push a rebase, it removes my ability to see the diff between what I reviewed previously and the current state

So generally, please prefer just layering on additional commits in the PR and we can squash/merge at the end. Not really anything better about this workflow other than GitHub supports it better

[damccorm]

Thanks! One more minor comment, otherwise this LGTM

[codecov]

Codecov Report

Attention: Patch coverage is 82.12291% with 32 lines in your changes missing coverage. Please review.

Project coverage is 57.41%. Comparing base (d9092a5) to head (9637269).
Report is 13 commits behind head on master.

Files with missing lines	Patch %	Lines
...ks/python/apache_beam/ml/rag/chunking/langchain.py	51.35%	18 Missing ⚠️
...ython/apache_beam/ml/rag/embeddings/huggingface.py	68.42%	6 Missing ⚠️
sdks/python/apache_beam/ml/transforms/base.py	91.22%	5 Missing ⚠️
...pache_beam/ml/transforms/embeddings/huggingface.py	0.00%	2 Missing ⚠️
sdks/python/apache_beam/ml/rag/chunking/base.py	95.83%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #33364      +/-   ##
============================================
+ Coverage     57.40%   57.41%   +0.01%     
  Complexity     1475     1475              
============================================
  Files           973      978       +5     
  Lines        154794   154935     +141     
  Branches       1076     1076              
============================================
+ Hits          88854    88959     +105     
- Misses        63737    63773      +36     
  Partials       2203     2203              

Flag	Coverage Δ
python	81.25% <82.12%> (-0.02%)	⬇️

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[damccorm]

Thanks - LGTM. The failing precommit seems to be related to flink, not this PR, so not blocking on that