* fix(terminal): stop claiming a Linux environment — point at the env section; near-neutral tokens
* feat(terminal): default GIT_PAGER/PAGER=cat in session env; drop schema lines the runtime already enforces; fix pty backend claim
* refactor(terminal): unify notify_on_complete+watch_patterns into notify (bool|list); trim pipe-masking prose (runtime hint owns it)
* fix(terminal): background param referenced the unadvertised legacy arg name
* refactor(terminal): background-only modifiers (pty, notify) fail loud on foreground calls with corrected shape
* fix(execute_code): block the new notify arg in the sandbox terminal stub (foreground-only)