Consolidate SSO redirects through `/_matrix/client/v3/login/sso/redir… #4107

Job	Run time
check-lockfile	8s
changes	1s
lint-newsfile	0s
lint-crlf	6s
lint	20s
check-schema-delta	42s
check-sampleconfig	38s
lint-clippy	27s
lint-clippy-nightly	27s
Typechecking	1m 31s
lint-pydantic	41s
lint-readme	9s
lint-rustfmt	22s
linting-done	3s
calculate-test-jobs	6s
trial-olddeps	6m 59s
complement (monolith, SQLite)	14m 10s
cargo-test	0s
portdb (3.9, 11)	3m 4s
complement (monolith, Postgres)	14m 28s
portdb (3.13, 17)	3m 16s
complement (workers, Postgres)	22m 7s
trial-pypy	0s
cargo-bench	0s
sytest (bullseye)	8m 34s
trial (3.9, sqlite, all)	5m 55s
sytest (bullseye, postgres)	10m 44s
trial (3.10, sqlite, all)	5m 34s
sytest (bullseye, multi-postgres, workers)	13m 17s
trial (3.11, sqlite, all)	4m 24s
sytest (bullseye, multi-postgres, workers, asyncio)	18m 55s
trial (3.12, sqlite, all)	5m 25s
sytest (bullseye, asyncio)	10m 18s
trial (3.13, sqlite, all)	5m 15s
sytest (bullseye, postgres, asyncio)	11m 46s
trial (3.9, postgres, 11, all)	14m 19s
sytest (testing, postgres)	11m 2s
trial (3.13, postgres, 17, all)	13m 36s
trial (3.9, sqlite)	5m 36s
export-data	2m 17s
tests-done	1s
	3h 36m 43s

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