host: review fixes for cargo.build, the test runner, the console, and main; tests for every PROTOCOL.md rule

cargo.build and the runner (review T22R): builds use the network again;
core.unlock and core.notify in order under the runner; quiet test
output; manifest preparation keeps [workspace], target tables, renamed
and optional entries; cargo.rpc.discover; -32004 with data.output;
retention of 10 builds; light, empty test worlds with an in-memory
journal; only CARGO_/RUST_/SAUSAGE_ variables; stdin is null; the runner
through --config. A compile cache that cannot be created is not fatal.
Activation replaces plugin.wasm without a gap.

Console and main: init ships the workspace Cargo.lock and creates the
world atomically; each console command runs in its own task, so ps,
stop, and kill work during a slow call; SAUSAGE_HEADLESS; the terminal
mode is restored; signals during boot; chat text is not taken as a
command.

Tests: 20 more tests for PROTOCOL.md sections 2 to 10; the cargo tests
choose the libtest binary from cargo's JSON output and time out.

cli/src/journal.rs

@@ -23,6 +23,9 @@ pub(crate) struct Journal {
     warned: Mutex<HashSet<String>>,
 }
 impl Journal {
+    pub(crate) async fn memory() -> anyhow::Result<Self> {
+        Self::open(PathBuf::from(":memory:")).await
+    }
     pub(crate) async fn open(path: PathBuf) -> anyhow::Result<Self> {
         let (sender, receiver) = mpsc::channel();
         let (ready, initialized) = oneshot::channel();
@@ -80,7 +83,9 @@ impl Journal {
     }
 }
 fn open_database(path: PathBuf) -> anyhow::Result<Connection> {
-    std::fs::create_dir_all(path.parent().unwrap())?;
+    if path != std::path::Path::new(":memory:") {
+        std::fs::create_dir_all(path.parent().unwrap())?;
+    }
     let db = Connection::open(path)?;
     db.execute_batch("PRAGMA journal_mode=WAL;
         PRAGMA synchronous=NORMAL;