refactor: rename RDReaderView -> RDEpubReaderView, update pod config and docs

- Rename source module from RDReaderView to RDEpubReaderView
- Move all source files from Sources/RDReaderView/ to Sources/RDEpubReaderView/
- Update podspec: RDReaderView.podspec -> RDEpubReaderView.podspec
- Update Podfile, demo project, and CocoaPods config for new pod name
- Delete old RDReaderView pod support files from ReadViewDemo/Pods
- Add new RDEpubReaderView pod support files
- Update documentation (API ref, architecture, UML, conventions, etc.)
- Add FixedLayoutRotationTests
- Update .gitignore: exclude .DS_Store, manual unpack backups, _ssoft-output

Sources/RDEpubReaderView/EPUBUI/Notes/RDEPUBNotePopupCoordinator.swift

@@ -0,0 +1,24 @@
+import UIKit
+
+final class RDEPUBNotePopupCoordinator {
+
+    static func present(
+        _ note: RDEPUBResolvedNote,
+        from controller: UIViewController,
+        onReturnToSource: (() -> Void)? = nil,
+        onOpenNoteLocation: (() -> Void)? = nil
+    ) {
+        let popup = RDEPUBNotePopupViewController(
+            note: note,
+            onReturnToSource: onReturnToSource,
+            onOpenNoteLocation: onOpenNoteLocation
+        )
+        let navigationController = UINavigationController(rootViewController: popup)
+        navigationController.modalPresentationStyle = .pageSheet
+        if let sheet = navigationController.sheetPresentationController {
+            sheet.detents = [.medium(), .large()]
+            sheet.prefersGrabberVisible = true
+        }
+        controller.present(navigationController, animated: true)
+    }
+}