Commit Message: "Compiled" static header maps instead of big trie
Additional Description: This is slightly slower for "misses" but significantly faster for "hits". Given that the majority of headers are expected to be matches for the static table, this should be a big win. (Each faster hit pays for 30 slower misses!) This structure also uses significantly less memory than the big trie.

Performance benchmarks - bazel run -c opt test/common/http:header_map_impl_speed_test -- --benchmark_filter="bm*" --benchmark_repetitions=25 --benchmark_display_aggregates_only

Benchmark	before	after	beforeStdDev	afterStdDev	change
bmHeaderMapImplRequestStaticLookupHits	47.2ns	16.4ns	0.629	0.378	-65.3%
bmHeaderMapImplResponseStaticLookupHits	34.7ns	14.3ns	0.571	0.085	-58.8%
bmHeaderMapImplRequestStaticLookupMisses	6.89ns	6.83ns	0.044	0.034	-0.01%
bmHeaderMapImplResponseStaticLookupMisses	6.40ns	7.31ns	0.028	0.057	+14.2%

Risk Level: Could be high since headers are parsed millions of times per second. But also there's a lot of existing test cases.
Testing: Added tests, existing tests involving headers will also provide coverage.
Docs Changes: n/a
Release Notes: Not yet
Platform Specific Features: n/a

Request variables

Key	Value
ref	fb5a879
sha	56c5e4e
pr	33932
base-sha	e1c31c3
actor	@ravenblackx
message	"Compiled" static header maps instead of big trie...
started	1715962685.196405
target-branch	main
trusted	false

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