feat(rust): RunicNPC is required in the Rust bundle (runicnpc stage 9, D310)

- install/update refuse a Rust bundle that carries no RunicNPC, before anything
  is written, and say how to get one that does.
- doctor fails when RunicNPC is missing or was never installed; a file edited
  by hand stays a warning, since it still loads.
- compose-bundles.sh composes no Rust bundle without a RunicNPC release that
  answers the bridge's runicnpc_api (the published one stays), and fails a
  bridge that declares none; every Rust bundle now has `npc`.
- A RunicNPC API-mismatch message lost its line continuation; restored.

The bundle type still parses a bundle without `npc`, so doctor and an old pin
can name it.

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

src/rustgame/install.rs

@@ -183,7 +183,9 @@ pub fn deploy(cli: &Cli, mode: Mode) -> Result<()> {
         );
     }
 
-    // RunicNPC (D224), fetched and checked beside the plugin, before anything is planned.
+    // RunicNPC (D224), fetched and checked beside the plugin, before anything is planned. It is
+    // required since RunicNPC's stage 9 (D310): the bridge refuses every NPC an event places
+    // without it, so a bundle that cannot place it is refused before anything is written.
     let npc_released = match &bundle.npc {
         Some(component) => {
             let path = scratch.path().join(&component.asset.name);
@@ -191,7 +193,8 @@ pub fn deploy(cli: &Cli, mode: Mode) -> Result<()> {
             let released = npc::read_tarball(&path)?;
             if released.manifest.api != component.api {
                 bail!(
-                    "RunicNPC in bundle {} answers API {}, but the bundle says {} — refusing a                      component the bundle does not describe.",
+                    "RunicNPC in bundle {} answers API {}, but the bundle says {} — refusing a \
+                     component the bundle does not describe.",
                     bundle.bundle,
                     released.manifest.api,
                     component.api
@@ -205,7 +208,12 @@ pub fn deploy(cli: &Cli, mode: Mode) -> Result<()> {
             }
             Some(released)
         }
-        None => None,
+        None => bail!(
+            "bundle {} carries no RunicNPC, and Runic Gateway's Rust events need it: without it \
+             the bridge refuses every NPC an event places. Install the current bundle (leave \
+             --bundle off), or pin one published with RunicNPC v1.0.0 or later.",
+            bundle.bundle
+        ),
     };
 
     // ── Plan every instance ──────────────────────────────────────────────────