mod: Phase 2a - add mod settings, I18n strings, and main.cpp integration

CrossPointSettings: Add mod-specific enums and fields:
- Clock: CLOCK_FORMAT, CLOCK_SIZE, TIMEZONE, clockFormat, clockSize,
  timezone, timezoneOffsetHours, autoNtpSync
- Sleep: SLEEP_SCREEN_LETTERBOX_FILL, sleepScreenLetterboxFill
- Reader: preferredPortrait, preferredLandscape
- Indexing: INDEXING_DISPLAY, indexingDisplay
- getTimezonePosixStr() for POSIX TZ string generation

main.cpp: Integrate mod initialization:
- OPDS store loading, boot NTP sync, timezone application
- Clock refresh loop (re-render on minute change)
- RTC time logging on boot

SettingsList.h: Add clock, timezone, and letterbox fill settings
JsonSettingsIO.cpp: Handle int8_t timezoneOffsetHours separately
I18n: Add ~80 mod string keys (english.yaml + regenerated I18nKeys.h)

Made-with: Cursor

src/main.cpp

@@ -12,17 +12,21 @@
 #include <SPI.h>
 #include <builtinFonts/all.h>
 
+#include <cstdlib>
 #include <cstring>
+#include <ctime>
 
 #include "CrossPointSettings.h"
 #include "CrossPointState.h"
 #include "KOReaderCredentialStore.h"
 #include "MappedInputManager.h"
+#include "OpdsServerStore.h"
 #include "RecentBooksStore.h"
 #include "activities/Activity.h"
 #include "activities/ActivityManager.h"
 #include "components/UITheme.h"
 #include "fontIds.h"
+#include "util/BootNtpSync.h"
 #include "util/ButtonNavigator.h"
 #include "util/ScreenshotUtil.h"
 
@@ -255,8 +259,15 @@ void setup() {
   HalSystem::clearPanic();  // TODO: move this to an activity when we have one to display the panic info
 
   SETTINGS.loadFromFile();
+
+  // Apply saved timezone setting on boot
+  setenv("TZ", SETTINGS.getTimezonePosixStr(), 1);
+  tzset();
+
   I18N.loadSettings();
   KOREADER_STORE.loadFromFile();
+  OPDS_STORE.loadFromFile();
+  BootNtpSync::start();
   UITheme::getInstance().reload();
   ButtonNavigator::setMappedInputManager(mappedInputManager);
 
@@ -281,6 +292,18 @@ void setup() {
   // First serial output only here to avoid timing inconsistencies for power button press duration verification
   LOG_DBG("MAIN", "Starting CrossPoint version " CROSSPOINT_VERSION);
 
+  // Log RTC time on boot for debugging
+  {
+    time_t now = time(nullptr);
+    struct tm* t = localtime(&now);
+    if (t != nullptr && t->tm_year > 100) {
+      LOG_DBG("MAIN", "RTC time: %04d-%02d-%02d %02d:%02d:%02d", t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
+              t->tm_hour, t->tm_min, t->tm_sec);
+    } else {
+      LOG_DBG("MAIN", "RTC time not set (epoch)");
+    }
+  }
+
   setupDisplayAndFonts();
 
   activityManager.goToBoot();
@@ -376,6 +399,28 @@ void loop() {
     return;
   }
 
+  // Refresh screen when the displayed minute changes (clock in header)
+  if (SETTINGS.clockFormat != CrossPointSettings::CLOCK_OFF) {
+    static int lastRenderedMinute = -1;
+    static bool sawInvalidTime = false;
+    time_t now = time(nullptr);
+    struct tm* t = localtime(&now);
+    if (t != nullptr && t->tm_year > 100) {
+      const int currentMinute = t->tm_hour * 60 + t->tm_min;
+      if (lastRenderedMinute < 0) {
+        lastRenderedMinute = currentMinute;
+        if (sawInvalidTime) {
+          activityManager.requestUpdate();
+        }
+      } else if (currentMinute != lastRenderedMinute) {
+        activityManager.requestUpdate();
+        lastRenderedMinute = currentMinute;
+      }
+    } else {
+      sawInvalidTime = true;
+    }
+  }
+
   const unsigned long activityStartTime = millis();
   activityManager.loop();
   const unsigned long activityDuration = millis() - activityStartTime;