feat: add InTEX iOS project and refresh agent guide

InTEX/InTEXTests/InTEXTests.swift

@@ -0,0 +1,19 @@
+//
+//  InTEXTests.swift
+//  InTEXTests
+//
+//  Created by allenyuan on 2026/6/27.
+//
+
+import Testing
+@testable import InTEX
+
+struct InTEXTests {
+
+    @Test func example() async throws {
+        // Write your test here and use APIs like `#expect(...)` to check expected conditions.
+        // Swift Testing Documentation
+        // https://developer.apple.com/documentation/testing
+    }
+
+}