- DEFAULT_WS_WRITE_TIMEOUT (60 s, WS-01 knob family): one outbound WS
send that stays unsent past the window (peer stopped reading)
evicts the connection — the send path was slot-bounded but
time-unbounded
- bound is per send call: a slow-but-draining peer resets it with
every message emitted; only a fully stalled sink trips it
- on timeout the pump signals the stream error (InvalidData naming
the write stall) and ends WITHOUT a close frame — a clogged socket
cannot receive one and the close send would park on it
- test-support split helper with both knobs explicit backs the
scaled eviction test (clogged duplex, eviction well inside the
5 s slack)
Verification: scripts/verify.sh OK (343 passed), clippy -D warnings
clean, fmt clean