Remove all RDEPUBBackgroundTrace.log and bare print diagnostic calls

Keep only the evaluateFullPageMapTakeover: fullReplace diagnostic log
in RDEPUBPageMapReconciliationCoordinator.swift for future debugging.

Simplified RDEPUBBackgroundTrace to just the log method (removed measure
and debug gating). Removed all [EPUB][...], [ReadViewDemo], and
[EPUB][Pagination] print statements across the project.

Also includes earlier bug fixes:
- Fix stale currentPageNumber in extendPartial commit
- Fix pageCurl rebindVisiblePage during transition
- Fix keepCurrentWindow not removing pending update from queue
- Fix right-aligned text (巫鸿 bug) via avoidPageBreakInside,
  tail merger, and continuation paragraph normalization
- Add text-indent reset for aligned blocks in CSS compatibility layer

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

Sources/RDReaderView/EPUBUI/ReaderController/ChapterRuntime/RDEPUBBackgroundTrace.swift

@@ -2,59 +2,9 @@ import Foundation
 
 enum RDEPUBBackgroundTrace {
 
-    static var isEnabled: Bool {
-#if DEBUG
-        return _enabled
-#else
-        return false
-#endif
-    }
-
-    static var _enabled = true
-
     static func log(_ scope: String, _ message: String) {
-        guard isEnabled else { return }
         let threadRole = Thread.isMainThread ? "main" : "bg"
-
-        let threadName = resolvedThreadName()
-
-        let queueLabel = resolvedQueueLabel()
-        print("[EPUB][\(scope)][\(threadRole)][queue=\(queueLabel)][thread=\(threadName)] \(message)")
+        let queueLabel = String(validatingUTF8: __dispatch_queue_get_label(nil)) ?? "unknown"
+        print("[EPUB][\(scope)][\(threadRole)][queue=\(queueLabel)] \(message)")
     }
-
-    static func measure<T>(_ scope: String, _ message: String, work: () throws -> T) rethrows -> T {
-        guard isEnabled else { return try work() }
-        let startedAt = CFAbsoluteTimeGetCurrent()
-        log(scope, "START \(message)")
-        do {
-
-            let result = try work()
-
-            let elapsedMs = Int((CFAbsoluteTimeGetCurrent() - startedAt) * 1000)
-            log(scope, "END \(message) elapsedMs=\(elapsedMs)")
-            return result
-        } catch {
-
-            let elapsedMs = Int((CFAbsoluteTimeGetCurrent() - startedAt) * 1000)
-            log(scope, "FAIL \(message) elapsedMs=\(elapsedMs) error=\(error)")
-            throw error
-        }
-    }
-
-    private static func resolvedThreadName() -> String {
-
-        if let name = Thread.current.name, !name.isEmpty {
-            return name
-        }
-
-        if Thread.isMainThread {
-            return "main"
-        }
-
-        return String(describing: Unmanaged.passUnretained(Thread.current).toOpaque())
-    }
-
-    private static func resolvedQueueLabel() -> String {
-        String(validatingUTF8: __dispatch_queue_get_label(nil)) ?? "unknown"
-    }
-}
+}