feat: stream search API

[forshev]

Description

Add new StreamSearch method. Add new seq-ql pipes: limit, offset, stats, sort.
StreamSearch method calls the old two-phase search implementation.

This is the first part of a new query engine implementation.

Fixes #476

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[github-actions]

❌ PR Title Validation Failed
Please refer to CONTRIBUTING.md

[codecov-commenter]

Codecov Report

❌ Patch coverage is 71.59091% with 125 lines in your changes missing coverage. Please review.
✅ Project coverage is 71.27%. Comparing base (7cc2790) to head (d7ae318).

Files with missing lines	Patch %	Lines
proxyapi/grpc_stream_search.go	64.59%	52 Missing and 22 partials ⚠️
parser/seqql_pipes.go	79.00%	19 Missing and 19 partials ⚠️
asyncsearcher/async_searcher.go	0.00%	3 Missing and 1 partial ⚠️
proxyapi/grpc_v1.go	33.33%	2 Missing and 2 partials ⚠️
proxy/search/async.go	0.00%	3 Missing ⚠️
skipmaskmanager/skip_mask_manager.go	0.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #481      +/-   ##
==========================================
+ Coverage   71.16%   71.27%   +0.10%     
==========================================
  Files         232      233       +1     
  Lines       18466    18894     +428     
==========================================
+ Hits        13141    13466     +325     
- Misses       4343     4405      +62     
- Partials      982     1023      +41     

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