macOS: split AppMain into focused modules

apps/macos/Sources/Clawdis/ShellRunner.swift

@@ -0,0 +1,45 @@
+import ClawdisIPC
+import Foundation
+
+enum ShellRunner {
+    static func run(command: [String], cwd: String?, env: [String: String]?, timeout: Double?) async -> Response {
+        guard !command.isEmpty else { return Response(ok: false, message: "empty command") }
+
+        let process = Process()
+        process.executableURL = URL(fileURLWithPath: "/usr/bin/env")
+        process.arguments = command
+        if let cwd { process.currentDirectoryURL = URL(fileURLWithPath: cwd) }
+        if let env { process.environment = env }
+
+        let stdoutPipe = Pipe()
+        let stderrPipe = Pipe()
+        process.standardOutput = stdoutPipe
+        process.standardError = stderrPipe
+
+        do {
+            try process.run()
+        } catch {
+            return Response(ok: false, message: "failed to start: \(error.localizedDescription)")
+        }
+
+        let waitTask = Task.detached { () -> (Int32, Data, Data) in
+            process.waitUntilExit()
+            let out = stdoutPipe.fileHandleForReading.readDataToEndOfFile()
+            let err = stderrPipe.fileHandleForReading.readDataToEndOfFile()
+            return (process.terminationStatus, out, err)
+        }
+
+        if let timeout, timeout > 0 {
+            let nanos = UInt64(timeout * 1_000_000_000)
+            try? await Task.sleep(nanoseconds: nanos)
+            if process.isRunning {
+                process.terminate()
+                return Response(ok: false, message: "timeout")
+            }
+        }
+
+        let (status, out, err) = await waitTask.value
+        let combined = out.isEmpty ? err : out
+        return Response(ok: status == 0, message: status == 0 ? nil : "exit \(status)", payload: combined)
+    }
+}