fix(companion): keep serving after an automation failure

companion/Sources/RunnerTestCase.swift

@@ -4,6 +4,9 @@ import XCTest
 // in a run loop so the simulator process stays alive serving the protocol.
 final class RunnerTestCase: XCTestCase {
     func testServeForever() throws {
+        // A failed automation call must never end the test: the server has to
+        // keep serving so the host can recover and retry.
+        continueAfterFailure = true
         let server = try Server()
         server.start()
         RunLoop.current.run()