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

lib/I18n/translations/english.yaml

@@ -341,3 +341,81 @@ STR_LINK: "[link]"
 STR_SCREENSHOT_BUTTON: "Take screenshot"
 STR_AUTO_TURN_ENABLED: "Auto Turn Enabled: "
 STR_AUTO_TURN_PAGES_PER_MIN: "Auto Turn (Pages Per Minute)"
+
+STR_CAT_CLOCK: "Clock"
+STR_CLOCK: "Clock"
+STR_CLOCK_AMPM: "AM/PM"
+STR_CLOCK_24H: "24 Hour"
+STR_SET_TIME: "Set Time"
+STR_CLOCK_SIZE: "Clock Size"
+STR_CLOCK_SIZE_SMALL: "Small"
+STR_CLOCK_SIZE_MEDIUM: "Medium"
+STR_CLOCK_SIZE_LARGE: "Large"
+STR_TIMEZONE: "Timezone"
+STR_TZ_UTC: "UTC"
+STR_TZ_EASTERN: "Eastern"
+STR_TZ_CENTRAL: "Central"
+STR_TZ_MOUNTAIN: "Mountain"
+STR_TZ_PACIFIC: "Pacific"
+STR_TZ_ALASKA: "Alaska"
+STR_TZ_HAWAII: "Hawaii"
+STR_TZ_CUSTOM: "Custom"
+STR_SET_UTC_OFFSET: "Set UTC Offset"
+STR_SYNC_CLOCK: "Sync Clock"
+STR_TIME_SYNCED: "Time synced!"
+STR_AUTO_NTP_SYNC: "Auto Sync on Boot"
+STR_LETTERBOX_FILL: "Letterbox Fill"
+STR_DITHERED: "Dithered"
+STR_SOLID: "Solid"
+STR_ADD_BOOKMARK: "Add Bookmark"
+STR_REMOVE_BOOKMARK: "Remove Bookmark"
+STR_LOOKUP_WORD: "Lookup Word"
+STR_LOOKUP_HISTORY: "Lookup Word History"
+STR_GO_TO_BOOKMARK: "Go to Bookmark"
+STR_CLOSE_BOOK: "Close Book"
+STR_DELETE_DICT_CACHE: "Delete Dictionary Cache"
+STR_DEFAULT_OPTION: "Default"
+STR_BOOKMARK_ADDED: "Bookmark added"
+STR_BOOKMARK_REMOVED: "Bookmark removed"
+STR_DICT_CACHE_DELETED: "Dictionary cache deleted"
+STR_NO_CACHE_TO_DELETE: "No cache to delete"
+STR_TABLE_OF_CONTENTS: "Table of Contents"
+STR_TOGGLE_ORIENTATION: "Toggle Portrait/Landscape"
+STR_TOGGLE_FONT_SIZE: "Toggle Font Size"
+STR_OVERRIDE_LETTERBOX_FILL: "Override Letterbox Fill"
+STR_PREFERRED_PORTRAIT: "Preferred Portrait"
+STR_PREFERRED_LANDSCAPE: "Preferred Landscape"
+STR_CHOOSE_SOMETHING: "Choose something to read"
+STR_INDEXING_DISPLAY: "Indexing Display"
+STR_INDEXING_POPUP: "Popup"
+STR_INDEXING_STATUS_TEXT: "Status Bar Text"
+STR_INDEXING_STATUS_ICON: "Status Bar Icon"
+STR_MANAGE_BOOK: "Manage Book"
+STR_ARCHIVE_BOOK: "Archive Book"
+STR_UNARCHIVE_BOOK: "Unarchive Book"
+STR_DELETE_BOOK: "Delete Book"
+STR_DELETE_CACHE_ONLY: "Delete Cache Only"
+STR_REINDEX_BOOK: "Reindex Book"
+STR_BROWSE_ARCHIVE: "Browse Archive"
+STR_BOOK_ARCHIVED: "Book archived"
+STR_BOOK_UNARCHIVED: "Book unarchived"
+STR_BOOK_DELETED: "Book deleted"
+STR_CACHE_DELETED: "Cache deleted"
+STR_BOOK_REINDEXED: "Book reindexed"
+STR_ACTION_FAILED: "Action failed"
+STR_BACK_TO_BEGINNING: "Back to Beginning"
+STR_CLOSE_MENU: "Close Menu"
+STR_ADD_SERVER: "Add Server"
+STR_SERVER_NAME: "Server Name"
+STR_NO_SERVERS: "No OPDS servers configured"
+STR_DELETE_SERVER: "Delete Server"
+STR_DELETE_CONFIRM: "Delete this server?"
+STR_OPDS_SERVERS: "OPDS Servers"
+STR_SAVE_HERE: "Save Here"
+STR_SELECT_FOLDER: "Select Folder"
+STR_DOWNLOAD_PATH: "Download Path"
+STR_POSITION: "Position"
+STR_DOWNLOAD_COMPLETE: "Download Complete!"
+STR_OPEN_BOOK: "Open Book"
+STR_BACK_TO_LISTING: "Back to Listing"
+STR_AFTER_DOWNLOAD: "After Download"