libtmux:switch-client

Switch captured terminal TARGET to SESSION and return a COMMAND-OUTCOME. CLIENT is the connection owning both observations. UPDATE-ENVIRONMENT defaults NIL, preserving the destination session environment; true applies tmux's update-environment option using TARGET's environment. OBSERVE defaults true and supplies a replacement attached-client through OUTCOME-VALUE. Earlier captures stay unchanged; failed follow-up acquisition stays in OUTCOME-OBSERVATION-ERROR. Blocks for preflight, dispatch and optional observation under shared limits. Preflight checks the unique client name and PID/creation/tty fingerprint; tmux does not atomically guard that fingerprint at dispatch. A changed or foreign target signals STALE-TARGET. Operational failures retain their outcome; no mutation is retried. Control clients are not supported by this operation.