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

Sources/RDReaderView/EPUBCore/RDEPUBPaginator.swift

@@ -53,9 +53,7 @@ public final class RDEPUBPaginator: NSObject {
         webView.scrollView.showsVerticalScrollIndicator = false
         webView.isUserInteractionEnabled = false
         if #available(iOS 16.4, *) {
-            webView.isInspectable = true
-        } else {
-            // Fallback on earlier versions
+            webView.isInspectable = RDEPUBWebViewDebug.isInspectableEnabled
         }
         RDEPUBWebViewDebug.log("PaginatorWebView", message: "configured webView=\(RDEPUBWebViewDebug.webViewID(webView))")
         return webView
@@ -297,6 +295,9 @@ public final class RDEPUBPaginator: NSObject {
         return mediaType.contains("html") || mediaType.contains("xhtml") || mediaType.contains("xml")
     }
 
+    /// 各轮测量记录值（用于稳定性日志）
+    private var measurementPassValues: [Int] = []
+
     /// 调度多轮测量：0ms/80ms/180ms 三轮延迟，取最大值以应对布局抖动
     private func scheduleMeasurementPass() {
         let sessionID = activeSessionID
@@ -306,8 +307,18 @@ public final class RDEPUBPaginator: NSObject {
                   let currentSpineIndex = currentSpineIndexForMeasurement() else {
                 return
             }
-            pageCounts[currentSpineIndex] = max(1, pendingMeasurementValue)
+            let finalValue = max(1, pendingMeasurementValue)
+            // 测量稳定性日志：三轮差异过大时告警
+            if measurementPassValues.count >= 2 {
+                let minVal = measurementPassValues.min() ?? 1
+                let maxVal = measurementPassValues.max() ?? 1
+                if minVal > 0 && Double(maxVal - minVal) / Double(minVal) > 0.2 {
+                    RDEPUBWebViewDebug.log(debugScope, message: "measurement instability: passes=\(measurementPassValues) spine=\(currentSpineIndex)")
+                }
+            }
+            pageCounts[currentSpineIndex] = finalValue
             currentMeasurementOffset += 1
+            measurementPassValues = []
             measureNextSpineItem()
             return
         }
@@ -333,8 +344,10 @@ public final class RDEPUBPaginator: NSObject {
             }
             if let number = value as? NSNumber {
                 self.pendingMeasurementValue = max(self.pendingMeasurementValue, number.intValue)
+                self.measurementPassValues.append(number.intValue)
             } else if let intValue = value as? Int {
                 self.pendingMeasurementValue = max(self.pendingMeasurementValue, intValue)
+                self.measurementPassValues.append(intValue)
             }
             RDEPUBWebViewDebug.log(self.debugScope, message: "measurement value=\(self.pendingMeasurementValue) session=\(sessionID)")
             self.scheduleMeasurementPass()
@@ -344,6 +357,20 @@ public final class RDEPUBPaginator: NSObject {
 }
 
 extension RDEPUBPaginator: WKNavigationDelegate {
+    public func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
+        guard let url = navigationAction.request.url else {
+            decisionHandler(.cancel)
+            return
+        }
+        let scheme = url.scheme?.lowercased() ?? ""
+        if scheme == "file" || scheme == RDEPUBResourceURLSchemeHandler.scheme {
+            decisionHandler(.allow)
+        } else {
+            RDEPUBWebViewDebug.log(debugScope, message: "blocked navigation to non-local scheme: \(scheme)")
+            decisionHandler(.cancel)
+        }
+    }
+
     public func webView(_ webView: WKWebView, didStartProvisionalNavigation navigation: WKNavigation!) {
         RDEPUBWebViewDebug.logNavigationEvent(debugScope, webView: webView, event: "didStart", url: webView.url)
     }