Fix iOS build: handle mesh transfer verbs/events in RemoteStore switches

The P4/P5 mesh work added ClientMsg cases (addressUpdate, transferOffer/Chunk/Commit/Cancel)
and SyncClient.Event cases (transferAccept/Reject/Ready/Committed/ChunkAck) but never updated
the iOS RemoteStore's two exhaustive switches — the demo-simulator ClientMsg handler and the
event handler — so NucleicRemote failed to compile ("switch must be exhaustive"). The app target
isn't built by `swift build`, so this landed unnoticed on the branch.

Both are inert on the phone: it's never a transfer source/destination and demo has no peer Macs,
so the new cases join the passive `break`. Verified with an iOS Simulator build (BUILD SUCCEEDED),
which also confirms this session's moved/arrived-provenance rendering edits compile.

Co-Authored-By: Claude Opus 4.8 <[email protected]>

NucleicRemote/NucleicRemote/Models/RemoteStore.swift

@@ -816,7 +816,10 @@ final class RemoteStore: ObservableObject {
         case .setSessionShipBranch(let id, let branch):
             demoUpdateSession(id) { $0.demoCopy(shipBranch: .some(branch)) }
         case .hello, .listSessions, .listDashboard, .subscribe, .unsubscribe,
-             .ping, .cancelQueuedMessage, .fetchDiff, .listPeers:
+             .ping, .cancelQueuedMessage, .fetchDiff, .listPeers, .addressUpdate,
+             // Session transfer (mesh P5) is a Mac↔Mac flow — the phone never originates these,
+             // and demo has no peer Macs, so they're inert here.
+             .transferOffer, .transferChunk, .transferCommit, .transferCancel:
             break  // passive / already handled by the seeded fixtures (demo has no mesh peers)
         }
     }
@@ -1072,6 +1075,10 @@ final class RemoteStore: ObservableObject {
             // Mesh P4: the host's known peers, for the (future) mesh device list and transfer
             // picker. Recorded now so multi-host UI can render it; single-host builds ignore it.
             meshPeers = peers
+        case .transferAccept, .transferReject, .transferReady, .transferCommitted, .transferChunkAck:
+            // Session-transfer replies (mesh P5) only reach a *source* Mac driving a transfer; a
+            // phone is never a transfer source, so these are inert here.
+            break
         case .wireError(let error):
             // A channel mismatch means the host and this remote were built from incompatible
             // release channels. Surface it as a persistent failure with a clear message rather