集成 MJRefresh 并重构主 TabBar 为系统 TabView 样式。

新增 SwiftUI 桥接层与单元测试，更新 Tab 图标资源命名和多倍图，同步调整 UI Test 的 Tab/扫码定位逻辑。

Co-authored-by: Cursor <cursoragent@cursor.com>

suixinkanTests/MJRefreshSupportTests.swift

@@ -0,0 +1,38 @@
+//
+//  MJRefreshSupportTests.swift
+//  suixinkanTests
+//
+//  Created by Codex on 2026/6/26.
+//
+
+import XCTest
+@testable import suixinkan
+
+/// MJRefresh SwiftUI 桥接测试，覆盖滚动视图查找辅助逻辑。
+final class MJRefreshSupportTests: XCTestCase {
+    /// 测试锚点视图能向上找到最近的 UIScrollView。
+    func testEnclosingScrollViewFindsParentScrollView() {
+        let scrollView = UIScrollView(frame: CGRect(x: 0, y: 0, width: 320, height: 480))
+        let container = UIView(frame: scrollView.bounds)
+        let anchor = UIView(frame: .zero)
+        scrollView.addSubview(container)
+        container.addSubview(anchor)
+
+        XCTAssertIdentical(anchor.enclosingScrollView, scrollView)
+    }
+
+    /// 测试没有父级 ScrollView 时返回 nil。
+    func testEnclosingScrollViewReturnsNilWithoutScrollView() {
+        let view = UIView(frame: .zero)
+        XCTAssertNil(view.enclosingScrollView)
+    }
+}
+
+extension MJRefreshSupportTests {
+    /// 断言两个对象引用相同。
+    fileprivate func XCTAssertIdentical(_ expression1: AnyObject?, _ expression2: AnyObject?, file: StaticString = #filePath, line: UInt = #line) {
+        if expression1 !== expression2 {
+            XCTFail("Expected identical objects", file: file, line: line)
+        }
+    }
+}