feat: `SSEResponse` class for streaming Server-Side Events #14199

Job	Run time
Setup PHP Version for Code Coverage	2s
Others (8.5) / Sanity Tests	2m 27s
Others (8.4) / Sanity Tests	2m 36s
Others (8.2) / Sanity Tests	3m 46s
Others (8.3) / Sanity Tests	2m 38s
CacheLive (8.3) / Cache Live Tests	2m 21s
SeparateProcess (8.4) / tests	3m 28s
SeparateProcess (8.2) / tests	3m 37s
DatabaseLive (8.3, Postgre, 8.0) / tests	2m 40s
CacheLive (8.5) / Cache Live Tests	2m 19s
DatabaseLive (8.2, OCI8, 8.0) / tests	7m 42s
DatabaseLive (8.4, MySQLi, 8.0) / tests	5m 19s
DatabaseLive (8.2, SQLite3, 8.0) / tests	2m 56s
SeparateProcess (8.3) / tests	3m 47s
CacheLive (8.2) / Cache Live Tests	2m 37s
DatabaseLive (8.3, MySQLi, 8.0) / tests	4m 39s
CacheLive (8.4) / Cache Live Tests	2m 15s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 36s
DatabaseLive (8.5, SQLite3, 8.0) / tests	2m 22s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	6m 4s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 9s
DatabaseLive (8.4, OCI8, 8.0) / tests	7m 16s
DatabaseLive (8.5, OCI8, 8.0) / tests	6m 47s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 54s
DatabaseLive (8.5, Postgre, 8.0) / tests	2m 55s
DatabaseLive (8.5, SQLSRV, 8.0) / tests	5m 9s
DatabaseLive (8.3, OCI8, 8.0) / tests	7m 16s
DatabaseLive (8.2, MySQLi, 5.7) / tests	3m 56s
SeparateProcess (8.5) / tests	3m 28s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 14s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	6m 50s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 32s
DatabaseLive (8.5, MySQLi, 8.0) / tests	6m 15s
DatabaseLive (8.2, MySQLi, 8.0) / tests	5m 18s
Upload coverage results to Coveralls / coveralls	51s
	2h 16m 1s

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