TerminalError gains SESSION_CLOSING, SESSION_EXITED, STARTUP_EXITED,
STARTUP_TIMEOUT, NO_SANDBOX, and INIT_REJECTED, following its existing
unprefixed code style. The terminal service and terminal-bash use them
for a send to a closing or exited session, a shell that exits or misses
readiness during startup, and a confined mode without a sandbox
provider; an empty confined argv is SubprocessError
SUBPROCESS_INVALID_ARGV, and a send on an aborted signal throws an
error named AbortError.
The persistent bash and pwsh tools report a missing owner as
ToolContextUnavailableError, a blank command as ToolArgsError, and a
shell that rejects its setup as TerminalError INIT_REJECTED.
Refs #7869
sjw1231
3538757cbe