Prevent repeated Computer Use helper launch dialogs

Packages/macOS/CmuxComputerUse/Sources/CmuxComputerUse/ComputerUseHelperLaunchConfiguration.swift

@@ -1,3 +1,4 @@
+import AppKit
 import Foundation
 import CmuxFoundation
 
@@ -6,6 +7,29 @@ struct ComputerUseHelperLaunchConfiguration: Equatable, Sendable {
     let arguments: [String]
     let environment: [String: String]
 
+    @MainActor
+    func workspaceConfiguration(
+        helperURL: URL,
+        fileManager: FileManager = .default
+    ) -> NSWorkspace.OpenConfiguration? {
+        let executable = helperURL.appendingPathComponent("Contents/MacOS/cmux-cua")
+        guard
+            let attributes = try? fileManager.attributesOfItem(atPath: executable.path),
+            attributes[.type] as? FileAttributeType == .typeRegular,
+            fileManager.isExecutableFile(atPath: executable.path)
+        else { return nil }
+
+        let configuration = NSWorkspace.OpenConfiguration()
+        configuration.activates = false
+        configuration.createsNewApplicationInstance = true
+        // Health checks retry in the background. Launch failures must reach the
+        // completion handler without waiting on another Finder error dialog.
+        configuration.promptsUserIfNeeded = false
+        configuration.arguments = arguments
+        configuration.environment = environment
+        return configuration
+    }
+
     init?(
         paths: ComputerUseRuntimePaths,
         profile: ComputerUseDaemonProfile = .native,

Packages/macOS/CmuxComputerUse/Sources/CmuxComputerUse/ComputerUseRuntimeService.swift

@@ -1146,11 +1146,9 @@ public final class ComputerUseRuntimeService {
             return false
         }
 
-        let configuration = NSWorkspace.OpenConfiguration()
-        configuration.activates = false
-        configuration.createsNewApplicationInstance = true
-        configuration.arguments = launch.arguments
-        configuration.environment = launch.environment
+        guard let configuration = launch.workspaceConfiguration(helperURL: helperURL) else {
+            return false
+        }
         let launchedProcessIdentifier: pid_t? = await withCheckedContinuation { continuation in
             NSWorkspace.shared.openApplication(
                 at: helperURL,

Packages/macOS/CmuxComputerUse/Tests/CmuxComputerUseTests/ComputerUseHelperLaunchConfigurationTests.swift

@@ -0,0 +1,70 @@
+import AppKit
+import Foundation
+import Testing
+@testable import CmuxComputerUse
+
+@MainActor
+struct ComputerUseHelperLaunchConfigurationTests {
+    @Test(arguments: ComputerUseDaemonProfile.allCases)
+    func backgroundLaunchDoesNotWaitForUserToDismissErrors(
+        profile: ComputerUseDaemonProfile
+    ) throws {
+        let fixture = try HelperBundleFixture()
+        defer { fixture.remove() }
+        let launch = try makeLaunch(fixture: fixture, profile: profile)
+        let configuration = try #require(launch.workspaceConfiguration(helperURL: fixture.bundle))
+
+        #expect(!configuration.promptsUserIfNeeded)
+        #expect(!configuration.activates)
+        #expect(configuration.createsNewApplicationInstance)
+        #expect(configuration.arguments == launch.arguments)
+        #expect(configuration.environment == launch.environment)
+    }
+
+    @Test func nonExecutableHelperIsRejectedUntilPermissionsAreRepaired() throws {
+        let fixture = try HelperBundleFixture()
+        defer { fixture.remove() }
+        let launch = try makeLaunch(fixture: fixture)
+        try FileManager.default.setAttributes(
+            [.posixPermissions: 0o644], ofItemAtPath: fixture.executable.path
+        )
+
+        #expect(launch.workspaceConfiguration(helperURL: fixture.bundle) == nil)
+        #expect(!FileManager.default.isExecutableFile(atPath: fixture.executable.path))
+
+        try FileManager.default.setAttributes(
+            [.posixPermissions: 0o755], ofItemAtPath: fixture.executable.path
+        )
+        #expect(launch.workspaceConfiguration(helperURL: fixture.bundle) != nil)
+    }
+
+    @Test func missingExecutableAndDirectoryAreRejected() throws {
+        let fixture = try HelperBundleFixture()
+        defer { fixture.remove() }
+        let launch = try makeLaunch(fixture: fixture)
+        try FileManager.default.removeItem(at: fixture.executable)
+        #expect(launch.workspaceConfiguration(helperURL: fixture.bundle) == nil)
+
+        try FileManager.default.createDirectory(
+            at: fixture.executable, withIntermediateDirectories: false
+        )
+        #expect(launch.workspaceConfiguration(helperURL: fixture.bundle) == nil)
+    }
+
+    private func makeLaunch(
+        fixture: HelperBundleFixture,
+        profile: ComputerUseDaemonProfile = .native
+    ) throws -> ComputerUseHelperLaunchConfiguration {
+        try #require(ComputerUseHelperLaunchConfiguration(
+            paths: ComputerUseRuntimePaths(
+                homeDirectoryURL: fixture.root,
+                socketRootDirectoryURL: fixture.root,
+                environment: [:],
+                bundleIdentifier: "com.cmuxterm.tests.helper-launch",
+                authenticationToken: "test-token",
+                hostAuthenticationToken: "test-host-token"
+            ),
+            profile: profile
+        ))
+    }
+}