fix(rust): the handoff says what the run did, not that a link exists (D156)

`install --game rust` ended every instance with "Rust server "alpha" is
connected to its sidecar" — printed unconditionally, before the plugin had
dialled anything, on a stopped server where it had not even loaded, and
beside "No service was registered, so nothing is listening yet". The
phase 18 walk read it as a claim and then found beta's plugin connected to
the wrong sidecar.

It now reads "Rust server "alpha" is set up." followed by either "The
plugin loads now; `doctor --game rust --server-id alpha` confirms it
connected." or "The plugin connects when the server next starts.".

The top-level --help no longer describes `install` as the uo-link sidecar
and overlay for both games, and says what `uninstall` removes for Rust.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

src/rustgame/sidecar.rs

@@ -152,12 +152,17 @@ pub fn choose_port(start: u16, held: &[u16], keep: Option<u16>) -> Result<u16> {
 }
 
 /// The end-of-run block for one instance: what `/admin/rust/servers` asks for.
+///
+/// It says what the run did, not what it hopes: nothing here has seen the plugin connect — on a
+/// stopped server it has not even loaded — so the first line never claims a link. `doctor` is the
+/// command that checks one (D156).
 pub fn handoff(
     server_id: &str,
     doc: &ConfigDoc,
     host: &str,
     site_url: Option<&str>,
     registered: bool,
+    running: bool,
 ) -> String {
     let port = port_of(&doc.web.bind)
         .map(|p| p.to_string())
@@ -167,7 +172,7 @@ pub fn handoff(
         .unwrap_or_else(|| "https://<your-site>".to_string());
     let loopback = doc.web.bind.starts_with("127.") || doc.web.bind.starts_with("[::1]");
     format!(
-        "\nRust server {server_id:?} is connected to its sidecar.\n\n\
+        "\nRust server {server_id:?} is set up. {when}\n\n\
          One manual step remains — add it to the website:\n\n  \
          Server id         {server_id}\n  \
          Sidecar URL       http://{host}:{port}\n  \
@@ -178,6 +183,13 @@ pub fn handoff(
         token = doc.web.auth_token,
         config = doc.config_path,
         protocol = doc.protocol,
+        when = if running {
+            format!(
+                "The plugin loads now; `doctor --game rust --server-id {server_id}` confirms it                  connected."
+            )
+        } else {
+            "The plugin connects when the server next starts.".to_string()
+        },
         loopback_note = if loopback {
             format!(
                 "\nThe sidecar listens on {} only. If the website runs on another machine, put a \
@@ -229,7 +241,7 @@ mod tests {
         )
         .unwrap();
         assert_eq!(port_of(&doc.web.bind), Some(8091));
-        let text = handoff("alpha", &doc, "rust.example", None, true);
+        let text = handoff("alpha", &doc, "rust.example", None, true, false);
         for needle in [
             "alpha",
             "http://rust.example:8091",
@@ -240,6 +252,19 @@ mod tests {
             assert!(text.contains(needle), "{needle} missing from:\n{text}");
         }
         assert!(text.contains("TLS proxy"), "{text}");
+
+        // D156: never a claim about a link nothing has seen.
+        assert!(!text.contains("is connected"), "{text}");
+        assert!(
+            text.contains("The plugin connects when the server next starts."),
+            "{text}"
+        );
+        let running = handoff("alpha", &doc, "rust.example", None, true, true);
+        assert!(!running.contains("is connected"), "{running}");
+        assert!(
+            running.contains("doctor --game rust --server-id alpha"),
+            "{running}"
+        );
     }
 
     #[test]