feat(proto): SurfaceState + SetState command + State event + SurfaceView.state

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/spacesh-proto/src/message.rs

@@ -1,6 +1,7 @@
 use serde::{Deserialize, Serialize};
 use crate::ids::{GroupId, SurfaceId, WorkspaceId};
 use crate::layout::LayoutNode;
+use crate::status::SurfaceState;
 use crate::workspace::{Group, WorkspaceView};
 
 /// Wire envelope. `kind` is the serde tag.
@@ -114,6 +115,7 @@ pub enum Cmd {
         order: Option<u32>,
     },
     DeleteGroup { group_id: GroupId },
+    SetState { surface_id: SurfaceId, state: SurfaceState },
     Status,
     Shutdown,
 }
@@ -131,6 +133,7 @@ pub enum Evt {
     WorkspaceClosed { workspace_id: WorkspaceId },
     GroupsChanged { groups: Vec<Group> },
     SurfaceRestarted { surface_id: SurfaceId },
+    State { surface_id: SurfaceId, state: SurfaceState },
 }
 
 #[cfg(test)]
@@ -240,4 +243,23 @@ mod tests {
         let back: Envelope = serde_json::from_str(&serde_json::to_string(&evt).unwrap()).unwrap();
         assert_eq!(back, evt);
     }
+
+    #[test]
+    fn set_state_round_trips() {
+        let env = Envelope::Req {
+            id: 1,
+            cmd: Cmd::SetState { surface_id: SurfaceId("s_1".into()), state: crate::status::SurfaceState::Done },
+        };
+        let back: Envelope = serde_json::from_str(&serde_json::to_string(&env).unwrap()).unwrap();
+        assert_eq!(back, env);
+    }
+
+    #[test]
+    fn state_event_round_trips() {
+        let evt = Envelope::Evt(Evt::State { surface_id: SurfaceId("s_1".into()), state: crate::status::SurfaceState::Wait });
+        let j = serde_json::to_string(&evt).unwrap();
+        assert!(j.contains(r#""evt":"state""#));
+        let back: Envelope = serde_json::from_str(&j).unwrap();
+        assert_eq!(back, evt);
+    }
 }