完善搜索定位与内存监测回归验证

本次提交围绕搜索链路的稳定性、定位恢复体验以及长章节内存优化的验证能力进行了补强。

主要改动：

1. 调整阅读器搜索栏、搜索协调器与定位恢复逻辑，改善搜索结果跳转、状态同步与相关 UI 行为。

2. 补充内存探针接入点与上下文记录，便于跟踪阅读过程中的内存占用变化。

3. 更新 RDURLReaderController、ReaderContext 与工具视图相关实现，使调试与观测链路更完整。

4. 新增 MemoryFootprintTests，并同步更新 DemoReaderState 与 SearchTests，用 UI 测试覆盖搜索与内存相关回归场景。

ReadViewDemo/ReadViewDemoUITests/ReaderUITests/SearchTests.swift

@@ -209,7 +209,9 @@ final class SearchTests: XCTestCase {
         XCTAssertFalse(searchBar.waitForExistence(timeout: 2), "关闭后搜索栏应消失")
     }
 
-    // MARK: - 搜索栏与工具栏联动
+    // MARK: - 搜索面板与工具栏联动（全屏面板模型）
+    // 全屏搜索面板覆盖内容区，面板打开时无法点击内容切换 chrome；
+    // 选中结果后面板关闭（搜索状态保留），chrome 隐藏/恢复联动面板。
 
     func testSearchBarHidesWhenToolbarsHide() {
         app.launchAndOpenSampleBook(searchKeyword: "的")
@@ -217,12 +219,15 @@ final class SearchTests: XCTestCase {
         app.showReaderChromeIfNeeded()
 
         let searchBar = app.otherElements[IDs.searchBar]
-        XCTAssertTrue(searchBar.waitForExistence(timeout: 10), "搜索栏应可见")
+        XCTAssertTrue(searchBar.waitForExistence(timeout: 10), "搜索面板应可见")
 
-        // 隐藏工具栏
+        // 选中结果后面板关闭并跳转，搜索状态保留
+        selectSearchResult(at: 0)
+        XCTAssertFalse(searchBar.waitForExistence(timeout: 2), "选中结果后搜索面板应关闭")
+
+        // 隐藏工具栏，面板应保持关闭
         app.hideReaderChromeIfNeeded()
-
-        XCTAssertFalse(searchBar.waitForExistence(timeout: 2), "工具栏隐藏时搜索栏也应隐藏")
+        XCTAssertFalse(searchBar.waitForExistence(timeout: 2), "工具栏隐藏时搜索面板应保持关闭")
     }
 
     func testSearchBarRestoresWhenToolbarsShow() {
@@ -233,13 +238,14 @@ final class SearchTests: XCTestCase {
         let searchBar = app.otherElements[IDs.searchBar]
         XCTAssertTrue(searchBar.waitForExistence(timeout: 10))
 
-        // 隐藏工具栏
+        // 选中结果关闭面板，再隐藏工具栏
+        selectSearchResult(at: 0)
         app.hideReaderChromeIfNeeded()
         XCTAssertFalse(searchBar.waitForExistence(timeout: 2))
 
-        // 重新显示工具栏
+        // 重新显示工具栏：搜索状态存在时面板应自动恢复
         app.showReaderChromeIfNeeded()
-        XCTAssertTrue(searchBar.waitForExistence(timeout: 3), "工具栏恢复时搜索栏也应恢复")
+        XCTAssertTrue(searchBar.waitForExistence(timeout: 3), "工具栏恢复时搜索面板也应恢复")
 
         // 搜索状态应保留
         let countLabel = app.staticTexts[IDs.searchCount]
@@ -286,6 +292,9 @@ final class SearchTests: XCTestCase {
         }
         let rangeCFIBefore = stateBefore.rangeCFI
 
+        // 全屏面板挡住工具栏，先选中当前匹配关闭面板（保留搜索状态）
+        selectSearchResult(at: 0)
+
         // 改变字体触发重排
         app.showReaderChromeIfNeeded()
         let settingsButton = app.buttons[IDs.readerSettings]
@@ -304,8 +313,8 @@ final class SearchTests: XCTestCase {
         }
         Thread.sleep(forTimeInterval: 1)
 
-        // 重新打开搜索并导航到匹配
-        app.showReaderChromeIfNeeded()
+        // 重新打开搜索面板（搜索状态保留），前后导航强制重解析当前命中
+        reopenSearchPanel()
         let prevButton = app.buttons[IDs.searchPrevious]
         let nextButton = app.buttons[IDs.searchNext]
         if prevButton.waitForExistence(timeout: 3), prevButton.isEnabled {
@@ -349,6 +358,9 @@ final class SearchTests: XCTestCase {
             return
         }
 
+        // 全屏面板挡住工具栏，先选中当前匹配关闭面板（保留搜索状态）
+        selectSearchResult(at: 0)
+
         // 改变字体大小触发重新排版
         app.showReaderChromeIfNeeded()
         let settingsButton = app.buttons[IDs.readerSettings]
@@ -367,15 +379,9 @@ final class SearchTests: XCTestCase {
         }
         Thread.sleep(forTimeInterval: 1)
 
-        // 测试多个匹配位置的跳转正确性
-        let nextButton = app.buttons[IDs.searchNext]
-        let prevButton = app.buttons[IDs.searchPrevious]
-        XCTAssertTrue(nextButton.waitForExistence(timeout: 3), "下一个按钮应存在")
-        XCTAssertTrue(prevButton.waitForExistence(timeout: 3), "上一个按钮应存在")
-
-        // 导航到第 2 个匹配，记录页码
-        nextButton.tap()
-        Thread.sleep(forTimeInterval: 0.5)
+        // 跳到第 2 个匹配，记录页码
+        reopenSearchPanel()
+        selectSearchResult(at: 1)
         let stateMatch2 = app.waitForDemoReaderState(timeout: 5, description: "match 2 page") {
             ($0.page ?? 0) > 0 && $0.rangeCFI?.isEmpty == false
         }
@@ -383,18 +389,11 @@ final class SearchTests: XCTestCase {
         let rangeCFIAtMatch2 = stateMatch2.rangeCFI
 
         // 翻到其他页
-        let content = app.otherElements[IDs.readerContent].firstMatch
-        if content.waitForExistence(timeout: 3) {
-            for _ in 0..<4 {
-                content.swipeLeft()
-                Thread.sleep(forTimeInterval: 0.3)
-            }
-            Thread.sleep(forTimeInterval: 0.5)
-        }
+        swipeAwayFromCurrentPage()
 
-        // 跳转到第 3 个匹配
-        nextButton.tap()
-        Thread.sleep(forTimeInterval: 0.5)
+        // 跳到第 3 个匹配
+        reopenSearchPanel()
+        selectSearchResult(at: 2)
         let stateMatch3 = app.waitForDemoReaderState(timeout: 5, description: "match 3 page") {
             ($0.page ?? 0) > 0 && $0.rangeCFI?.isEmpty == false
         }
@@ -402,17 +401,11 @@ final class SearchTests: XCTestCase {
         let rangeCFIAtMatch3 = stateMatch3.rangeCFI
 
         // 再翻到其他页
-        if content.waitForExistence(timeout: 3) {
-            for _ in 0..<4 {
-                content.swipeLeft()
-                Thread.sleep(forTimeInterval: 0.3)
-            }
-            Thread.sleep(forTimeInterval: 0.5)
-        }
+        swipeAwayFromCurrentPage()
 
         // 跳回第 2 个匹配，验证页码不变
-        prevButton.tap()
-        Thread.sleep(forTimeInterval: 0.5)
+        reopenSearchPanel()
+        selectSearchResult(at: 1)
         let stateBack2 = app.waitForDemoReaderState(timeout: 5, description: "back to match 2") {
             $0.page == pageAtMatch2 && $0.rangeCFI == rangeCFIAtMatch2
         }
@@ -422,17 +415,11 @@ final class SearchTests: XCTestCase {
             "重排后搜索跳回第 2 个匹配应命中同一段文本")
 
         // 再翻到其他页
-        if content.waitForExistence(timeout: 3) {
-            for _ in 0..<4 {
-                content.swipeLeft()
-                Thread.sleep(forTimeInterval: 0.3)
-            }
-            Thread.sleep(forTimeInterval: 0.5)
-        }
+        swipeAwayFromCurrentPage()
 
         // 跳到第 3 个匹配，验证页码不变
-        nextButton.tap()
-        Thread.sleep(forTimeInterval: 0.5)
+        reopenSearchPanel()
+        selectSearchResult(at: 2)
         let stateBack3 = app.waitForDemoReaderState(timeout: 5, description: "back to match 3") {
             $0.page == pageAtMatch3 && $0.rangeCFI == rangeCFIAtMatch3
         }
@@ -452,4 +439,39 @@ final class SearchTests: XCTestCase {
         let searchBar = app.otherElements[IDs.searchBar]
         XCTAssertTrue(searchBar.waitForExistence(timeout: 3), "搜索栏应出现")
     }
+
+    /// 点击全屏搜索面板中的结果行：跳转到对应匹配并关闭面板（搜索状态保留）
+    private func selectSearchResult(at matchIndex: Int) {
+        let cell = app.cells["epub.reader.search.result.\(matchIndex)"].firstMatch
+        XCTAssertTrue(cell.waitForExistence(timeout: 10), "搜索结果第 \(matchIndex) 项应存在")
+        cell.tap()
+        RunLoop.current.run(until: Date().addingTimeInterval(0.5))
+    }
+
+    /// 重新打开搜索面板。chrome 恢复时若有搜索状态面板会自动恢复；
+    /// chrome 本就可见时需点击工具栏搜索按钮。
+    private func reopenSearchPanel() {
+        app.showReaderChromeIfNeeded()
+        let searchBar = app.otherElements[IDs.searchBar]
+        if searchBar.waitForExistence(timeout: 2) {
+            return
+        }
+        let searchButton = app.buttons[IDs.readerSearch]
+        XCTAssertTrue(searchButton.waitForExistence(timeout: 3), "搜索按钮应存在")
+        searchButton.tap()
+        XCTAssertTrue(searchBar.waitForExistence(timeout: 3), "搜索面板应重新打开")
+    }
+
+    /// 隐藏 chrome 后向后翻若干页，使当前页离开搜索命中页
+    private func swipeAwayFromCurrentPage() {
+        app.hideReaderChromeIfNeeded()
+        let content = app.otherElements[IDs.readerContent].firstMatch
+        if content.waitForExistence(timeout: 3) {
+            for _ in 0..<4 {
+                content.swipeLeft()
+                Thread.sleep(forTimeInterval: 0.3)
+            }
+            Thread.sleep(forTimeInterval: 0.5)
+        }
+    }
 }