A foreground bash or pwsh call that waits on a job rethrew a failed
preparation as new Error(view.detail), dropping the original class and
code, so even SandboxUnavailableError reached tool/result without
error.name or error.code. processJob now keeps the original error for a
failed job and the tool rethrows it; launch and spawn rejections on
every path keep a HarnessError's identity, and a platform spawn error
becomes SubprocessError (SUBPROCESS_SPAWN_NOT_FOUND or _SPAWN_FAILED).
Argument violations are ToolArgsError, a missing sandboxing executor
for sandbox_permissions is SandboxEscalationError
SANDBOX_ESCALATION_UNAVAILABLE, a disabled background call is JobError
JOB_BACKGROUND_DISABLED, and a missing job runtime is
ToolContextUnavailableError.
Refs #7869
sjw1231