A member turn that failed without a typed gateway reason rendered as a bare
"X hit an error" — a stopped backend, a dead IPC bridge and a provider refusal
all looked identical and gave the user nothing to act on.
groupFailureReason now falls back to the error message's first non-empty
line (trimmed, secret-shaped spans redacted, capped at 200 chars), so the
Activity row reads "X hit an error — <cause>". Typed data.reason and the
slot-wait classification keep precedence; the roster badge still classifies
from the same text.
The plugin fence keeps the Electron-side redactSecrets out of reach, so the
same shapes (bearer header, ?token=/?api_key= params, vendor key prefixes,
user@host:password) live next to the label.
Fixes#117366
d90c3ad40a