Align Client SSE support to HTML specification #18075

Job	Run time
Build and Test (ubuntu-latest, 2.12.20, graal_graalvm@17)	3m 8s
Jmh CachedDateHeaderBenchmark	0s
Jmh ClientBenchmark	0s
Build and Test (ubuntu-latest, 2.12.20, graal_graalvm@21)	3m 6s
Jmh CookieDecodeBenchmark	0s
Jmh EndpointBenchmark	0s
Build and Test (ubuntu-latest, 2.12.20, temurin@17)	3m 7s
Jmh HttpCollectEval	0s
Jmh HttpCombineEval	0s
Build and Test (ubuntu-latest, 2.12.20, temurin@21)	3m 9s
Build and Test (ubuntu-latest, 2.13.16, graal_graalvm@17)	3m 6s
Jmh HttpNestedFlatMapEval	0s
Jmh HttpRouteTextPerf	0s
Build and Test (ubuntu-latest, 2.13.16, graal_graalvm@21)	3m 6s
Build and Test (ubuntu-latest, 2.13.16, temurin@17)	3m 8s
Jmh ProbeContentTypeBenchmark	0s
Jmh MethodLookupBenchmark	0s
Build and Test (ubuntu-latest, 2.13.16, temurin@21)	2m 51s
Jmh RoundtripBenchmark	0s
Build and Test (ubuntu-latest, 3.3.5, graal_graalvm@17)	3m 5s
Jmh RoutesBenchmark	0s
Build and Test (ubuntu-latest, 3.3.5, graal_graalvm@21)	3m 4s
Jmh SchemeDecodeBenchmark	0s
Jmh ServerInboundHandlerBenchmark	0s
Build and Test (ubuntu-latest, 3.3.5, temurin@17)	3m 8s
Jmh UtilBenchmark	0s
Build and Test (ubuntu-latest, 3.3.5, temurin@21)	3m 7s
Mima Check (ubuntu-latest, 2.13.10, temurin@21)	1m 56s
Performance Benchmarks (SimpleEffectBenchmarkServer) (ubuntu-latest, 2.13.16, zulu@8)	7m 55s
Performance Benchmarks (PlainTextBenchmarkServer) (ubuntu-latest, 2.13.16, zulu@8)	7m 57s
Unsafe Scoverage (ubuntu-latest, 2.13.16, zulu@8)	2m 24s
Cache Jmh benchmarks	0s
Publish Artifacts	0s
	57m 17s

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