feat: EPUB 阅读器搜索、选中注释、书签 chrome 状态及大量重构优化

- 新增 RDEPUBReaderSearchCoordinator 与 RDEPUBSelectionState 管理搜索和选中状态
- 新增 BookmarkChromeStateTests、NavigationBackwardTests、SelectionAnnotateTests 等 UI 测试
- 新增多个边界测试 epub 样本（损坏结构、空归档、缺失文件、流式外链验证）
- 重构阅读器 chrome 状态管理，统一 tool bar 与 search bar 交互
- 优化大书分页缓存策略（RDEPUBChapterSummaryDiskCache、RDEPUBPageCountCache）
- 移除废弃的 RDEPUBLocationConverter 和 RDEPUBPageBreakPolicy
- 更新 epub-bridge.js 与 JS bridge 通信协议
- 全面更新现有 UI 测试以适配新的 helper 和状态管理

ReadViewDemo/ReadViewDemoUITests/ReaderUITests/BookmarkManagementTests.swift

@@ -15,7 +15,7 @@ final class BookmarkManagementTests: XCTestCase {
         let bookmarkButton = app.buttons[IDs.readerBookmark]
         XCTAssertTrue(bookmarkButton.waitForExistence(timeout: 3), "书签按钮不存在")
         bookmarkButton.tap()
-        app.waitForReaderState(containing: "bookmarks=1", timeout: 5)
+        app.waitForDemoReaderState(timeout: 5, description: "bookmarks=1") { $0.bookmarks == 1 }
 
         app.showReaderChromeIfNeeded()
         let bookmarksButton = app.buttons[IDs.readerBookmarks]
@@ -47,7 +47,7 @@ final class BookmarkManagementTests: XCTestCase {
 
         app.showReaderChromeIfNeeded()
         app.buttons[IDs.readerBookmark].tap()
-        app.waitForReaderState(containing: "bookmarks=1", timeout: 5)
+        app.waitForDemoReaderState(timeout: 5, description: "bookmarks=1") { $0.bookmarks == 1 }
         app.showReaderChromeIfNeeded()
         app.buttons[IDs.readerBookmarks].tap()
 
@@ -78,6 +78,39 @@ final class BookmarkManagementTests: XCTestCase {
         XCTAssertTrue(bookmarkButton.waitForExistence(timeout: 3), "移除书签后按钮应仍然存在")
     }
 
+    func testBookmarksButtonDisabledWhenNoBookmarks() throws {
+        app.launchAndOpenSampleBook(resetsReaderState: true)
+        app.waitForReader(timeout: 12)
+
+        app.showReaderChromeIfNeeded()
+        let bookmarksButton = app.buttons[IDs.readerBookmarks]
+        XCTAssertTrue(bookmarksButton.waitForExistence(timeout: 3), "书签列表按钮不存在")
+        XCTAssertFalse(bookmarksButton.isEnabled, "零书签时书签列表按钮应禁用")
+    }
+
+    func testBookmarkIndicatorStaysSelectedAtBookmarkedLocation() throws {
+        app.launchAndOpenSampleBook(resetsReaderState: true)
+        app.waitForReader(timeout: 12)
+
+        app.showReaderChromeIfNeeded()
+        let bookmarkButton = app.buttons[IDs.readerBookmark]
+        XCTAssertTrue(bookmarkButton.waitForExistence(timeout: 3), "书签按钮不存在")
+        bookmarkButton.tap()
+        app.waitForDemoReaderState(timeout: 5, description: "bookmarks=1") { $0.bookmarks == 1 }
+        XCTAssertEqual(bookmarkButton.value as? String, "selected", "当前页已加书签时顶部书签按钮应为选中态")
+
+        let paging = app.collectionViews[IDs.readerPaging]
+        if paging.waitForExistence(timeout: 5) {
+            paging.swipeLeft()
+            app.showReaderChromeIfNeeded()
+            XCTAssertEqual(bookmarkButton.value as? String, "unselected", "离开书签页后顶部书签按钮应取消选中")
+
+            paging.swipeRight()
+            app.showReaderChromeIfNeeded()
+            XCTAssertEqual(bookmarkButton.value as? String, "selected", "返回书签页后顶部书签按钮应恢复选中")
+        }
+    }
+
     private func waitForCellCount(
         in table: XCUIElement,
         minimum: Int,