- StackRegion from /proc/<pid>/maps, exposed as state.stack
({top, usable_base, guard_size} BigInts per spec)
- until(loc) one-shot bp wrapper that cleans up via try/finally,
works even if a different stop fires first
- finish() reads return address from [rbp+8] and uses until()
- updated js.rs module doc; allow(dead_code) on the kept-for-future
BreakpointSet::find_by_name