- runAppBinary registers SIGINT and SIGTERM after its build and recursion
checks and runChild forwards each signal to the app binary, then waits
for it to exit, so stopping summer serve frees the port (WR-08)
- newAppCmd keeps the inherited stdin, env and output, and a context
cancel sends SIGTERM with a 15-second appShutdownGrace before SIGKILL
- the child stays in summer's process group so the admin password
prompts can read the terminal
- helper-process tests cover SIGINT, SIGTERM and context cancel
- console introduction notes the signal forwarding
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