Nucleic: Session Routing Logic Enhancement

NucleicRemote/NucleicRemote/Models/RemoteStore.swift

@@ -121,10 +121,13 @@ final class RemoteStore: ObservableObject {
         return (descriptor, candidates)
     }
 
-    /// Dispatch a new chat to the abstract **Mesh** destination from the phone: rank eligible
+    /// Dispatch a new chat to the abstract **Carbon** destination from the phone: rank eligible
     /// hosts by the shared scorer and try them in order, one at a time with a correlated,
     /// idempotent ack (a timeout retries the same candidate once before moving on). On success
-    /// routes to the landed session. Mirrors `AppStore.dispatchChatToMesh`.
+    /// routes to the landed session. Mirrors `AppStore.dispatchChatToMesh`. The phone stamps
+    /// itself as the Carbon origin, so the landed session is Carbon-managed (its owner keeps it
+    /// on the optimal host between turns); the phone can't own sessions, so the origin exclusion
+    /// is naturally satisfied by every candidate.
     func dispatchChatToMesh(
         projectID: ProjectID, message: String, model: String? = nil,
         effort: String? = nil, auto: Bool? = nil
@@ -141,8 +144,8 @@ final class RemoteStore: ObservableObject {
                     backend: nil, excluding: excluded).first
                 else {
                     showError(tried == 0
-                        ? "No mesh runner can take this chat right now."
+                        ? "No Carbon host can take this chat right now."
-                        : "No mesh runner could take this chat (\(tried) tried).", sessionID: nil)
+                        : "No Carbon host could take this chat (\(tried) tried).", sessionID: nil)
                     return
                 }
                 tried += 1
@@ -154,7 +157,8 @@ final class RemoteStore: ObservableObject {
                 let requestID = UUID().uuidString
                 let request = StartChatRequest(
                     projectID: targetProjectID, message: text, model: model, effort: effort,
-                    auto: auto, requestID: requestID)
+                    auto: auto, requestID: requestID,
+                    carbonOriginDeviceID: IdentityStore.deviceID())
                 var outcome = await sendDispatch(request, on: conn, timeout: .seconds(10))
                 if outcome == nil {
                     outcome = await sendDispatch(request, on: conn, timeout: .seconds(5))

NucleicRemote/NucleicRemote/Views/Composer.swift

@@ -18,8 +18,10 @@ struct StartChatComposer: View {
     /// project page's "+", so the chat always lands in that project.
     var lockedProject: WireProject? = nil
     @State private var projectID: ProjectID?
-    /// Mesh dispatch: run on the project's own Mac (false) or auto-route to the best eligible
+    /// Carbon (mesh work queue): run on the project's own Mac (false) or on Carbon (true) —
-    /// mesh host (true). Shown only when a connected peer could actually take it.
+    /// auto-routed to the best eligible mesh host and kept on the optimal host between turns.
+    /// The phone itself can't run sessions, so every Carbon candidate is already "not here".
+    /// Shown only when a connected peer could actually take it.
     @State private var runOnMesh = false
     @State private var autoOverride: Bool?
     @State private var model: String?
@@ -87,18 +89,19 @@ struct StartChatComposer: View {
                     ? "Auto-approve is always on for Nucleic Control chats — they run autonomously."
                     : "Auto-approve safe actions; destructive ones still ask.")
             }
-            // Mesh dispatch: when an eligible peer holds this repo, offer "Auto (Mesh)" so the
+            // Carbon (mesh work queue): when an eligible peer holds this repo, offer "Carbon" so
-            // chat routes to whichever host fits rather than always its own owner.
+            // the chat routes to whichever host fits — and moves between hosts as availability
+            // changes — rather than always running on its own owner.
             if meshAvailable {
                 Menu {
                     Picker("Run on", selection: $runOnMesh) {
                         Text("This Mac").tag(false)
-                        Text("Mesh (automatic)").tag(true)
+                        Text("Carbon").tag(true)
                     }
                     .pickerStyle(.inline)
                 } label: {
                     Label(
-                        runOnMesh ? "Mesh" : "This Mac",
+                        runOnMesh ? "Carbon" : "This Mac",
                         systemImage: runOnMesh ? "antenna.radiowaves.left.and.right" : "desktopcomputer")
                         .font(.caption)
                         .foregroundStyle(Palette.accent)