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/EPUBTextRendering/Pagination/RDEPUBTextPaginationInterfaces.swift

@@ -0,0 +1,32 @@
+
+import Foundation
+import UIKit
+
+struct RDEPUBPageBreakDecision {
+
+    var range: NSRange
+
+    var reason: RDEPUBTextPageBreakReason
+
+    var diagnostics: [String]
+}
+
+protocol RDEPUBChapterPageCounting {
+
+    func pageRanges(
+        for attributedString: NSAttributedString,
+        pageSize: CGSize,
+        config: RDEPUBTextLayoutConfig,
+        fragmentOffsets: [String: Int]
+    ) -> [RDEPUBPageBreakDecision]
+}
+
+protocol RDEPUBPageFrameBuilding {
+
+    func makeFrames(
+        attributedString: NSAttributedString,
+        pageSize: CGSize,
+        config: RDEPUBTextLayoutConfig,
+        fragmentOffsets: [String: Int]
+    ) -> [RDEPUBTextLayoutFrame]
+}