fix: resolve mod build errors after upstream sync

- Update open-x4-sdk submodule to 9f76376 (BatteryMonitor ESP-IDF 5.x compat)
- Add RTC_NOINIT bounds check for logHead in Logging.cpp
- Add drawTextRotated90CCW to GfxRenderer for dictionary UI
- Add getWordXpos() accessor to TextBlock for dictionary word selection
- Fix bare include paths (ActivityResult.h, RenderLock.h) across 10 files
- Fix rvalue ref binding in setResult() lambdas (std::move pattern)
- Fix std::max type mismatch (uint8_t vs int) in EpubReaderActivity
- Fix FsFile forward declaration conflict in Dictionary.h
- Restore StringUtils::checkFileExtension() and sortFileList()
- Restore RecentBooksStore::removeBook()

Made-with: Cursor

lib/Logging/Logging.cpp

@@ -10,7 +10,10 @@ RTC_NOINIT_ATTR char logMessages[MAX_LOG_LINES][MAX_ENTRY_LEN];
 RTC_NOINIT_ATTR size_t logHead = 0;
 
 void addToLogRingBuffer(const char* message) {
-  // Add the message to the ring buffer, overwriting old messages if necessary
+  // RTC_NOINIT memory may contain garbage after flash erase or power loss
+  if (logHead >= MAX_LOG_LINES) {
+    logHead = 0;
+  }
   strncpy(logMessages[logHead], message, MAX_ENTRY_LEN - 1);
   logMessages[logHead][MAX_ENTRY_LEN - 1] = '\0';
   logHead = (logHead + 1) % MAX_LOG_LINES;