Add cmuxterm CLI and socket control modes

Sources/SocketControlSettings.swift

@@ -0,0 +1,95 @@
+import Foundation
+
+enum SocketControlMode: String, CaseIterable, Identifiable {
+    case off
+    case notifications
+    case full
+
+    var id: String { rawValue }
+
+    var displayName: String {
+        switch self {
+        case .off:
+            return "Off"
+        case .notifications:
+            return "Notifications only"
+        case .full:
+            return "Full control"
+        }
+    }
+
+    var description: String {
+        switch self {
+        case .off:
+            return "Disable the local control socket."
+        case .notifications:
+            return "Allow only notification commands over the local socket."
+        case .full:
+            return "Allow all socket commands, including tab and input control."
+        }
+    }
+}
+
+struct SocketControlSettings {
+    static let appStorageKey = "socketControlMode"
+    static let legacyEnabledKey = "socketControlEnabled"
+
+    static var defaultMode: SocketControlMode {
+#if DEBUG
+        return .full
+#else
+        return .notifications
+#endif
+    }
+
+    static func socketPath() -> String {
+        if let override = ProcessInfo.processInfo.environment["CMUX_SOCKET_PATH"], !override.isEmpty {
+            return override
+        }
+#if DEBUG
+        return "/tmp/cmuxterm-debug.sock"
+#else
+        return "/tmp/cmuxterm.sock"
+#endif
+    }
+
+    static func envOverrideEnabled() -> Bool? {
+        guard let raw = ProcessInfo.processInfo.environment["CMUX_SOCKET_ENABLE"], !raw.isEmpty else {
+            return nil
+        }
+
+        switch raw.trimmingCharacters(in: .whitespacesAndNewlines).lowercased() {
+        case "1", "true", "yes", "on":
+            return true
+        case "0", "false", "no", "off":
+            return false
+        default:
+            return nil
+        }
+    }
+
+    static func envOverrideMode() -> SocketControlMode? {
+        guard let raw = ProcessInfo.processInfo.environment["CMUX_SOCKET_MODE"], !raw.isEmpty else {
+            return nil
+        }
+        return SocketControlMode(rawValue: raw.trimmingCharacters(in: .whitespacesAndNewlines).lowercased())
+    }
+
+    static func effectiveMode(userMode: SocketControlMode) -> SocketControlMode {
+        if let overrideEnabled = envOverrideEnabled() {
+            if !overrideEnabled {
+                return .off
+            }
+            if let overrideMode = envOverrideMode() {
+                return overrideMode
+            }
+            return userMode == .off ? .notifications : userMode
+        }
+
+        if let overrideMode = envOverrideMode() {
+            return overrideMode
+        }
+
+        return userMode
+    }
+}