header match based extproc

[PatilHrushikesh]

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #

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[codecov]

Codecov Report

❌ Patch coverage is 59.13043% with 47 lines in your changes missing coverage. Please review.
✅ Project coverage is 76.27%. Comparing base (2b40195) to head (bd230c9).

Files with missing lines	Patch %	Lines
internal/xds/translator/extproc.go	64.94%	24 Missing and 10 partials ⚠️
internal/gatewayapi/envoyextensionpolicy.go	27.77%	12 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9780      +/-   ##
==========================================
- Coverage   76.34%   76.27%   -0.07%     
==========================================
  Files         261      261              
  Lines       44440    44549     +109     
==========================================
+ Hits        33927    33980      +53     
- Misses       8269     8315      +46     
- Partials     2244     2254      +10     

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[zirain]

I think the underlying layer is more universal (at least not just ExtProc), so we probably need a more generic API shape.
cc @envoyproxy/gateway-maintainers

[PatilHrushikesh]

I think the underlying layer is more universal (at least not just ExtProc), so we probably need a more generic API shape. cc @envoyproxy/gateway-maintainers

so you are saying to have generic field for wasm and lua (and other) as well?