feat(query-engine): prototype streaming query engine

[forshev]

Summary

Introduces the foundation for a new streaming search engine that will enable searching by non-indexed fields.

Key Changes

• New Query Engine with streaming RecordProducer interface
• SeqQL parser extensions: filter, sort, limit, stats, fields pipes
• gRPC streaming API for one-phase search (store side)

Architecture

Instead of the traditional two-phase approach (find IDs → fetch documents), this engine streams documents directly through a chain of executors (filter → sort → limit → project), enabling efficient search on non-indexed fields.

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 58.38028% with 591 lines in your changes missing coverage. Please review.
✅ Project coverage is 69.90%. Comparing base (23d27e1) to head (5b47f6e).

Files with missing lines	Patch %	Lines
proxyapi/grpc_one_phase_search.go	0.00%	175 Missing ⚠️
proxyapi/grpc_v1.go	14.28%	80 Missing and 4 partials ⚠️
storeapi/grpc_one_phase_search.go	60.76%	64 Missing and 18 partials ⚠️
proxy/search/one_phase_search.go	53.98%	63 Missing and 12 partials ⚠️
parser/seqql_pipes.go	71.71%	32 Missing and 24 partials ⚠️
query/exec/data_source.go	76.19%	21 Missing and 14 partials ⚠️
storeapi/client.go	0.00%	25 Missing ⚠️
proxyapi/grpc_async_search.go	0.00%	16 Missing ⚠️
query/exec/merger.go	89.79%	9 Missing and 1 partial ⚠️
query/record.go	79.48%	6 Missing and 2 partials ⚠️
... and 7 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #360      +/-   ##
==========================================
- Coverage   70.83%   69.90%   -0.93%     
==========================================
  Files         225      236      +11     
  Lines       17512    18922    +1410     
==========================================
+ Hits        12404    13227     +823     
- Misses       4183     4691     +508     
- Partials      925     1004      +79     

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[github-actions]

🔴 Performance Degradation

Some benchmarks have degraded compared to the previous run.
Click on Show table button to see full list of degraded benchmarks.

Show table

Name	Previous	Current	Ratio	Verdict
AggWide/size=10000-4	8aefcc	afad98
	47761.00 ns/op	58671.00 ns/op	1.23	🔴
AggWide/size=1000000-4	8aefcc	afad98
	516.00 B/op	623.00 B/op	1.21	🔴
	5419714.00 ns/op	6613404.00 ns/op	1.22	🔴
FindSequence_Random/small-4	8aefcc	afad98
	6638.44 MB/s	5400.47 MB/s	0.81	🔴

[github-actions]

🔴 Performance Degradation

Some benchmarks have degraded compared to the previous run.
Click on Show table button to see full list of degraded benchmarks.

Show table

Name	Previous	Current	Ratio	Verdict
AggDeep/size=1000-4	8aefcc	5e2344
	4817.00 ns/op	5772.00 ns/op	1.20	🔴
AggDeep/size=1000000-4	8aefcc	5e2344
	4837044.00 ns/op	5950444.00 ns/op	1.23	🔴
AggWide/size=10000-4	8aefcc	5e2344
	47761.00 ns/op	57932.00 ns/op	1.21	🔴
FindSequence_Random/small-4	8aefcc	5e2344
	6638.44 MB/s	5084.65 MB/s	0.77	🔴

[github-actions]

🔴 Performance Degradation

Some benchmarks have degraded compared to the previous run.
Click on Show table button to see full list of degraded benchmarks.

Show table

Name	Previous	Current	Ratio	Verdict
AggWide/size=1000000-4	2c48a6	6a5e64
	467.00 B/op	545.00 B/op	1.17	🔴