feat: add support for new reduce proto

[kohlisid]

Fixes #1545

1. Add support for new proto specifications
2. Refactor reducer to include task manager

[codecov]

Codecov Report

Attention: Patch coverage is 97.12230% with 4 lines in your changes are missing coverage. Please review.

Project coverage is 95.24%. Comparing base (882302b) to head (5bfd9ea).

Files	Patch %	Lines
pynumaflow/reducer/servicer/async_servicer.py	92.00%	0 Missing and 2 partials ⚠️
pynumaflow/reducer/servicer/task_manager.py	96.87%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #133      +/-   ##
==========================================
+ Coverage   95.21%   95.24%   +0.02%     
==========================================
  Files          45       46       +1     
  Lines        1442     1513      +71     
  Branches       81       83       +2     
==========================================
+ Hits         1373     1441      +68     
- Misses         50       51       +1     
- Partials       19       21       +2     

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