feat: implement re filter

[dkharms]

Description

This PR introduces support for matching fields (indexed as keyword) against regular expressions.

Closes #347

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 75.00000% with 15 lines in your changes missing coverage. Please review.
✅ Project coverage is 71.51%. Comparing base (8e3ecad) to head (dd18a46).

Files with missing lines	Patch %	Lines
parser/token_re.go	65.38%	8 Missing and 1 partial ⚠️
parser/ast_node.go	0.00%	2 Missing ⚠️
parser/seqql_filter.go	75.00%	1 Missing and 1 partial ⚠️
pattern/pattern.go	75.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #348      +/-   ##
==========================================
- Coverage   71.52%   71.51%   -0.01%     
==========================================
  Files         204      205       +1     
  Lines       14812    14872      +60     
==========================================
+ Hits        10594    10636      +42     
- Misses       3454     3468      +14     
- Partials      764      768       +4     

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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.

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Name	Previous	Current	Ratio	Verdict
FindSequence_Deterministic/corner-cases-1-4	6ae568	54a732
	58.26 ns/op	65.76 ns/op	1.13	🔴
FindSequence_Random/small-4	6ae568	54a732
	5683.27 MB/s	4255.45 MB/s	0.75	🔴
	45.04 ns/op	60.16 ns/op	1.34	🔴
MutexListAppend-4	6ae568	54a732
	184.44 MB/s	161.62 MB/s	0.88	🔴
	86751404.00 ns/op	98998589.00 ns/op	1.14	🔴

[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.

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Name	Previous	Current	Ratio	Verdict
FindSequence_Random/small-4	6ae568	be91bd
	5683.27 MB/s	4722.01 MB/s	0.83	🔴
	45.04 ns/op	54.21 ns/op	1.20	🔴

[github-actions]

🔴 Performance Degradation

Some benchmarks have degraded compared to the previous run.
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Name	Previous	Current	Ratio	Verdict
ESBulk-4	b9c2c0	528ea7
	372.00 B/op	437.00 B/op	1.17	🔴
GenerateDocs-4	b9c2c0	528ea7
	935.60 ns/op	1048.00 ns/op	1.12	🔴

[github-actions]

🔴 Performance Degradation

Some benchmarks have degraded compared to the previous run.
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Name	Previous	Current	Ratio	Verdict
FindSequence_Random/medium-4	b9c2c0	ecd8ed
	10894.16 MB/s	6498.19 MB/s	0.60	🔴
	94.00 ns/op	157.60 ns/op	1.68	🔴

[github-actions]

🔴 Performance Degradation

Some benchmarks have degraded compared to the previous run.
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Name	Previous	Current	Ratio	Verdict
And/size=1000000-4	8e3eca	51947c
	4.58 ns/op	5.38 ns/op	1.17	🔴

[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	8e3eca	efbb6a
	4863.00 ns/op	5810.00 ns/op	1.19	🔴