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/RDEPUBTextLayoutFrame.swift

@@ -0,0 +1,38 @@
+import Foundation
+
+struct RDEPUBTextLayoutFrame: Equatable {
+
+    var contentRange: NSRange
+
+    var breakReason: RDEPUBTextPageBreakReason
+
+    var blockRange: NSRange?
+
+    var attachmentRanges: [NSRange]
+
+    var attachmentKinds: [RDEPUBTextAttachmentKind]
+
+    var blockKinds: [RDEPUBTextBlockKind]
+
+    var semanticHints: [RDEPUBTextSemanticHint]
+
+    var attachmentPlacements: [RDEPUBTextAttachmentPlacement]
+
+    var trailingFragmentID: String?
+
+    var diagnostics: [String]
+
+    var metadata: RDEPUBTextPageMetadata {
+        RDEPUBTextPageMetadata(
+            breakReason: breakReason,
+            blockRange: blockRange,
+            attachmentRanges: attachmentRanges,
+            attachmentKinds: attachmentKinds,
+            blockKinds: blockKinds,
+            semanticHints: semanticHints,
+            attachmentPlacements: attachmentPlacements,
+            trailingFragmentID: trailingFragmentID,
+            diagnostics: diagnostics
+        )
+    }
+}