Series values fetching reworked with protocol buffer support

[Raalsky]

Before submitting checklist

• Did you update the CHANGELOG? (not for test updates, internal changes/refactors or CI/CD setup)
• Did you ask the docs owner to review all the user-facing changes?

[codecov]

Codecov Report

Attention: Patch coverage is 83.33333% with 7 lines in your changes are missing coverage. Please review.

Project coverage is 76.91%. Comparing base (b6a168f) to head (b623f33).
Report is 3 commits behind head on master.

Files	Patch %	Lines
...eptune/internal/backends/hosted_neptune_backend.py	12.50%	7 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1744   +/-   ##
=======================================
  Coverage   76.91%   76.91%           
=======================================
  Files         244      245    +1     
  Lines       13016    13029   +13     
=======================================
+ Hits        10011    10021   +10     
- Misses       3005     3008    +3     

Flag	Coverage Δ
e2e	65.26% <30.95%> (+0.08%)	⬆️
e2e-management	55.95% <30.95%> (+0.08%)	⬆️
e2e-s3	53.08% <30.95%> (+0.10%)	⬆️
e2e-s3-gcs	53.08% <30.95%> (+0.10%)	⬆️
e2e-standard	65.25% <30.95%> (+0.14%)	⬆️
macos	76.78% <83.33%> (-0.07%)	⬇️
py3.10	?
py3.11	?
py3.12	65.37% <30.95%> (-11.80%)	⬇️
py3.7	76.30% <83.33%> (+0.08%)	⬆️
py3.7.16	64.38% <30.95%> (-11.71%)	⬇️
py3.8	?
py3.9	?
ubuntu	76.85% <83.33%> (+0.03%)	⬆️
unit	73.16% <83.33%> (-0.66%)	⬇️
windows	76.54% <83.33%> (+0.03%)	⬆️

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[Raalsky]

E2E: https://github.com/neptune-ai/neptune-client/actions/runs/8708895142

[szysad]

LGTM 🚀🚀