core: review fixes, init builds the agent, console without a terminal

Activation path (review T6R): a broken plugin or a stray file in
/plugins blocks no activation; candidates replace their own entries;
discovery has a 10 s deadline and its process is stopped after the
answer; an unchanged hash keeps plugin.prev.wasm; activations run in
their own task; the watcher is not recursive; no duplicate services;
rpc.retired waits for live processes of its version; reads and hashes
on blocking threads.

Guest I/O and per-call paths: a stdin write error is EOF, stdout and
stderr are drained before the status; stderr is lossy UTF-8 and goes
to the journal from its own reader; compiled components are freed;
shutdown starts no new processes; lock queues drop stopping processes;
compile before the admission gate; CommandPre per component;
core.unlock in order; null errors are successes; the journal thread
survives SQLite errors.

sausage init builds the agent with cargo.build; sausage without a
command creates ./world. The console reads plain lines without a
terminal. PROTOCOL.md and DECISIONS.md describe the decided rules. The
flake tests the whole workspace and checks the packaged cargo.build.

cli/src/locks.rs

@@ -15,6 +15,15 @@ impl Host {
     pub(crate) async fn lock(&self, caller: &str, path: &str, wait: bool) -> RpcResult {
         let rx = {
             let mut state = self.0.state.lock().unwrap();
+            if caller != "console"
+                && caller != "core"
+                && !state
+                    .processes
+                    .get(caller)
+                    .is_some_and(|p| p.info.state == "running")
+            {
+                return Err(error(-32600, "process is stopping or ended"));
+            }
             if let Some(lock) = state.locks.get_mut(path) {
                 if !wait {
                     return Ok(json!({"held":false}));