feat: chapter runtime refactoring and related updates

- Refactor chapter runtime: replace window coordinator/snapshot with warmup orchestrator
- Update EPUB core: parser, reading session, JS bridge, navigator layout
- Update reader controller: data source, location resolution, persistence
- Update chapter runtime: data cache, loader, runtime store, disk cache, warmup orchestrator
- Remove deprecated navigation state machine and pagination state
- Update text rendering: book cache, HTML normalizer
- Update UI: text content view, dark image adjuster, text selection controller
- Update settings and reader configuration
- Add CODE_REVIEW.md and AUDIT_FINAL.md documentation
- Update pod dependencies (remove SSAlertSwift, SnapKit)
- Update podspec and pod configuration files

Co-Authored-By: Claude <noreply@anthropic.com>

Sources/RDReaderView/EPUBTextRendering/BuildPipeline/RDEPUBTextBookCache.swift

@@ -104,7 +104,7 @@ final class ChapterPaginationArchive: NSObject, NSSecureCoding {
 
 public final class RDEPUBTextBookCache {
 
-    public var schemaVersion: Int = 13
+    public var schemaVersion: Int = 14
 
     private let queue = DispatchQueue(label: "com.rdreader.textbookcache", qos: .utility)
 

Sources/RDReaderView/EPUBTextRendering/Typesetter/RDEPUBHTMLNormalizer.swift

@@ -27,6 +27,7 @@ struct RDEPUBHTMLNormalizer: RDEPUBTypesettingStage {
         }
 
         cleanedHTML = normalizeAttachmentHTMLMarkers(in: cleanedHTML)
+        cleanedHTML = normalizeBodyLeadingSpacing(in: cleanedHTML)
         return cleanedHTML
     }
 
@@ -129,6 +130,64 @@ struct RDEPUBHTMLNormalizer: RDEPUBTypesettingStage {
         return normalized
     }
 
+    private static func normalizeBodyLeadingSpacing(in html: String) -> String {
+        var normalized = html
+
+        if let bodyStartRegex = try? NSRegularExpression(
+            pattern: #"(<body\b[^>]*>)\s+"#,
+            options: [.caseInsensitive]
+        ) {
+            normalized = bodyStartRegex.stringByReplacingMatches(
+                in: normalized,
+                options: [],
+                range: NSRange(location: 0, length: (normalized as NSString).length),
+                withTemplate: "$1"
+            )
+        }
+
+        if let bodyEndRegex = try? NSRegularExpression(
+            pattern: #"\s+(</body>)"#,
+            options: [.caseInsensitive]
+        ) {
+            normalized = bodyEndRegex.stringByReplacingMatches(
+                in: normalized,
+                options: [],
+                range: NSRange(location: 0, length: (normalized as NSString).length),
+                withTemplate: "$1"
+            )
+        }
+
+        guard let firstBlockRegex = try? NSRegularExpression(
+            pattern: #"(<body\b[^>]*>)(\s*)(<(?<tag>h[1-6]|p|div|blockquote|section|article|ul|ol)\b[^>]*>)"#,
+            options: [.caseInsensitive]
+        ) else {
+            return normalized
+        }
+
+        let nsNormalized = normalized as NSString
+        let fullRange = NSRange(location: 0, length: nsNormalized.length)
+        guard let match = firstBlockRegex.firstMatch(in: normalized, options: [], range: fullRange),
+              match.numberOfRanges >= 4,
+              let bodyRange = Range(match.range(at: 1), in: normalized),
+              let blockRange = Range(match.range(at: 3), in: normalized) else {
+            return normalized
+        }
+
+        let prefix = String(normalized[..<bodyRange.lowerBound])
+        let bodyTag = String(normalized[bodyRange])
+        let blockTag = String(normalized[blockRange])
+        let normalizedBlockTag = mergeHTMLAttributes(
+            into: blockTag,
+            requiredClass: nil,
+            styleFragments: [
+                "margin-top:0 !important",
+                "-webkit-margin-before:0 !important",
+                "padding-top:0 !important"
+            ]
+        )
+        return prefix + bodyTag + normalizedBlockTag + String(normalized[blockRange.upperBound...])
+    }
+
     static func replaceMatches(
         using regex: NSRegularExpression,
         in source: String,