feat(ios): W0 scaffold + day-1 spike + WireProtocol frozen contract + TestSupport doubles

T-iOS-1: ios/ XcodeGen project (iOS 17, Swift 6 strict concurrency, ATS per PLAN §5.2), 5 SPM package shells, CI skeleton
T-iOS-2: Origin spike vs real server — URLSessionWebSocketTask custom Origin CONFIRMED (no Starscream); 16MiB replay + EMSGSIZE(40) errno correction written back to plan
T-iOS-3: WireProtocol frozen contract, 59 tests, 100% line coverage, cross-impl vectors vs src/protocol.ts via tsx
T-iOS-4: FakeTransport/FakeClock/FakeHTTPTransport doubles
Verify: independent agent re-ran all acceptance — 6/6 PASS

ios/Packages/TestSupport/Tests/TestSupportTests/FakeTransportTests.swift

@@ -0,0 +1,41 @@
+import Foundation
+import Testing
+import WireProtocol
+@testable import TestSupport
+
+@Suite("FakeTransport")
+struct FakeTransportTests {
+    @Test("scripts connect failures, delivers injected frames, records sends and closes")
+    func scriptsFailuresDeliversFramesAndRecordsTraffic() async throws {
+        // Arrange
+        let transport = FakeTransport()
+        let baseURL = try #require(URL(string: "http://192.168.1.5:3000"))
+        let endpoint = try #require(HostEndpoint(baseURL: baseURL))
+        let attachFrame = #"{"type":"attach","sessionId":null}"#
+
+        // Act + Assert: a scripted failure makes the next connect throw it.
+        await transport.scriptConnectFailure()
+        await #expect(throws: FakeTransportError.scriptedConnectFailure) {
+            _ = try await transport.connect(to: endpoint)
+        }
+
+        // Act: connect for real, send one frame, inject one frame, close cleanly.
+        let connection = try await transport.connect(to: endpoint)
+        try await connection.send(attachFrame)
+        await transport.emit(frame: "server-frame-1")
+        await transport.finishFrames()
+
+        var received: [String] = []
+        for try await frame in connection.frames {
+            received.append(frame)
+        }
+        await connection.close()
+
+        // Assert: injected frames arrived in order and ended with a clean finish.
+        #expect(received == ["server-frame-1"])
+        // Assert: the double recorded everything the client did.
+        #expect(await transport.sentFrames == [attachFrame])
+        #expect(await transport.closeCallCount == 1)
+        #expect(await transport.connectAttempts == [endpoint, endpoint])
+    }
+}