pgsql: Move WAIT_FOR_WAL_* wait events from Client to IPC class

Move WAIT_FOR_WAL_* wait events from Client to IPC class

WAIT_FOR_WAL_FLUSH, WAIT_FOR_WAL_REPLAY, and WAIT_FOR_WAL_WRITE were
placed in the WaitEventClient class. But WaitEventClient is about
waiting for a socket to become readable or writable, while these events
have other delay sources as well: local fsync and local replay, which
may be disk- or CPU-bound. WaitEventIPC is a better fit, so move them
there.

Reported-by: Noah Misch <noah(at)leadboat(dot)com>
Discussion: https://postgr.es/m/20260706012642.f9.noahmisch@microsoft.com
Backpatch-through: 19

Branch
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REL_19_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/56fa044d15e8b06d84889f06f5def21a62fb86a3

Modified Files
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src/backend/utils/activity/wait_event_names.txt | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)