feat(macos): onboard Claude OAuth + identity

apps/macos/Sources/Clawdis/ClawdisConfigFile.swift

@@ -62,4 +62,28 @@ enum ClawdisConfigFile {
         root["inbound"] = inbound
         self.saveDict(root)
     }
+
+    static func loadIdentity() -> AgentIdentity? {
+        let root = self.loadDict()
+        guard let identity = root["identity"] as? [String: Any] else { return nil }
+        let name = identity["name"] as? String ?? ""
+        let theme = identity["theme"] as? String ?? ""
+        let emoji = identity["emoji"] as? String ?? ""
+        let result = AgentIdentity(name: name, theme: theme, emoji: emoji)
+        return result.isEmpty ? nil : result
+    }
+
+    static func setIdentity(_ identity: AgentIdentity?) {
+        var root = self.loadDict()
+        if let identity, !identity.isEmpty {
+            root["identity"] = [
+                "name": identity.name.trimmingCharacters(in: .whitespacesAndNewlines),
+                "theme": identity.theme.trimmingCharacters(in: .whitespacesAndNewlines),
+                "emoji": identity.emoji.trimmingCharacters(in: .whitespacesAndNewlines),
+            ]
+        } else {
+            root.removeValue(forKey: "identity")
+        }
+        self.saveDict(root)
+    }
 }