Reorganize docs and update reader search flows

Sources/RDReaderView/EPUBUI/TextPage/RDEPUBTextContentView.swift

@@ -489,6 +489,7 @@ final class RDEPUBTextContentView: UIView, UIGestureRecognizerDelegate {
 
     @objc private func handleLongPress(_ gesture: UILongPressGestureRecognizer) {
 #if canImport(DTCoreText)
+        layoutIfNeeded()
         selectionController.handleLongPress(
             gesture,
             renderView: coreTextRenderView,

Sources/RDReaderView/EPUBUI/TextPage/RDEPUBTextSelectionController.swift

@@ -60,10 +60,8 @@ final class RDEPUBTextSelectionController: NSObject {
         switch gesture.state {
         case .began, .changed:
             updateSelection(at: point, renderView: renderView, interactionController: interactionController)
-        case .ended:
+        case .ended, .cancelled, .failed:
             isSelecting = false
-        case .cancelled, .failed:
-            clearSelection(renderView: renderView)
         default:
             break
         }
@@ -89,7 +87,9 @@ final class RDEPUBTextSelectionController: NSObject {
         interactionController: RDEPUBPageInteractionController
     ) {
         guard let index = interactionController.characterIndexForViewPoint(at: point, in: renderView) else {
-            clearSelection(renderView: renderView)
+            if !isSelecting {
+                clearSelection(renderView: renderView)
+            }
             return
         }
         selectionStartIndex = index