feat: allow overriding SSE messages endpoint #2045

Job	Run time
checks / readme-snippets	11s
checks / pre-commit	36s
checks / test (3.11, lowest-direct, ubuntu-latest)	47s
checks / test (3.10, locked, ubuntu-latest)	52s
checks / test (3.10, lowest-direct, windows-latest)	3m 4s
checks / test (3.10, locked, windows-latest)	2m 55s
checks / test (3.12, lowest-direct, ubuntu-latest)	59s
checks / test (3.11, lowest-direct, windows-latest)	2m 44s
checks / test (3.12, locked, ubuntu-latest)	59s
checks / test (3.10, lowest-direct, ubuntu-latest)	58s
checks / test (3.12, lowest-direct, windows-latest)	3m 53s
checks / test (3.11, locked, ubuntu-latest)	50s
checks / test (3.14, locked, windows-latest)	3m 57s
checks / test (3.14, locked, ubuntu-latest)	2m 23s
checks / test (3.11, locked, windows-latest)	3m 1s
checks / test (3.14, lowest-direct, windows-latest)	2m 29s
checks / test (3.14, lowest-direct, ubuntu-latest)	1m 10s
checks / test (3.13, locked, ubuntu-latest)	46s
checks / test (3.13, lowest-direct, windows-latest)	3m 0s
checks / test (3.12, locked, windows-latest)	2m 36s
checks / test (3.13, lowest-direct, ubuntu-latest)	55s
checks / test (3.13, locked, windows-latest)	2m 39s
all-green	5s
	41m 49s

Provide feedback