feat: `SSEResponse` class for streaming Server-Side Events #14190

Job	Run time
Setup PHP Version for Code Coverage	2s
Others (8.5) / Sanity Tests	2m 44s
Others (8.2) / Sanity Tests	3m 55s
Others (8.4) / Sanity Tests	2m 40s
Others (8.3) / Sanity Tests	2m 39s
SeparateProcess (8.2) / tests	3m 51s
SeparateProcess (8.4) / tests	3m 27s
CacheLive (8.4) / Cache Live Tests	2m 18s
DatabaseLive (8.3, OCI8, 8.0) / tests	7m 17s
SeparateProcess (8.3) / tests	3m 27s
CacheLive (8.3) / Cache Live Tests	2m 23s
DatabaseLive (8.5, OCI8, 8.0) / tests	7m 3s
DatabaseLive (8.2, SQLite3, 8.0) / tests	3m 8s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 44s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 44s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 24s
DatabaseLive (8.5, SQLite3, 8.0) / tests	2m 13s
DatabaseLive (8.3, Postgre, 8.0) / tests	3m 6s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 23s
DatabaseLive (8.4, OCI8, 8.0) / tests	7m 8s
DatabaseLive (8.2, MySQLi, 5.7) / tests	3m 42s
DatabaseLive (8.2, OCI8, 8.0) / tests	7m 26s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 48s
CacheLive (8.5) / Cache Live Tests	2m 19s
DatabaseLive (8.2, MySQLi, 8.0) / tests	5m 19s
DatabaseLive (8.5, MySQLi, 8.0) / tests	4m 31s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	5m 50s
DatabaseLive (8.4, MySQLi, 8.0) / tests	4m 35s
DatabaseLive (8.3, MySQLi, 8.0) / tests	4m 9s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	6m 41s
SeparateProcess (8.5) / tests	3m 36s
DatabaseLive (8.5, SQLSRV, 8.0) / tests	5m 11s
DatabaseLive (8.5, Postgre, 8.0) / tests	2m 39s
CacheLive (8.2) / Cache Live Tests	2m 33s
Upload coverage results to Coveralls / coveralls	49s
	2h 13m 44s

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