feat(init): supervise servers+session progs: restart on death, same endpoint, backoff 0/1/5/30s then give up, restarts_clients cascade; release grants/spawn at stop (stale-slot safe); storage death fatal; init output via printer thread (never blocks on log); terminal Ctrl+C via CONTROL-badged copy, latest wins; flaky test server + spawntest restart/backoff check

crates/types/src/terminal.rs

@@ -12,11 +12,13 @@ pub const READ_SECRET: usize = 14;
 /// that drew on the screen itself.
 pub const REDRAW: usize = 12;
 /// Carries a notification the terminal signals on Ctrl+C while no line is
-/// being read. Accepted once a session (see `SIGNED_OUT`).
+/// being read. Only through a copy whose badge has `CONTROL`; the latest
+/// one counts, so a restarted shell simply registers again.
 pub const ON_INTERRUPT: usize = 13;
-/// From the unbadged holder (init) only, at sign-out: forgets who
-/// `ON_INTERRUPT` signals, so the next session's shell may register.
-pub const SIGNED_OUT: usize = 15;
+/// On the badge of the terminal copy init gives the program that takes
+/// Ctrl+C (the shell). The copies it passes on to apps carry its badge
+/// too, so it gives them its other, plain copy.
+pub const CONTROL: usize = 1 << 62;
 /// What Ctrl+C types.
 pub const CTRL_C: u8 = 3;