* Added support for external dictionary apps and a dictionary settings sheet.
* Refactored external dictionary integration and improved package visibility
- Updated `AndroidManifest.xml` with `<queries>` for common dictionary apps and intent actions (`PROCESS_TEXT`, `SEARCH`, `SEND`) to support Android 11+ package visibility.
- Refactored `ExternalDictionaryHelper` to streamline dictionary discovery using `Intent.ACTION_PROCESS_TEXT` and `colordict.intent.action.SEARCH`.
- Added a package blocklist in `ExternalDictionaryHelper` to filter out system services (e.g., Samsung Pass, GMS) from dictionary lists.
- Simplified `launchDictionary` logic to prioritize `PROCESS_TEXT` intents.
- Fixed a bug in `PdfViewerScreen` to only show the dictionary upsell dialog when `useOnlineDictionary` is enabled.
* Refactored dictionary settings into a dialog and updated dictionary selection logic.
- Renamed `DictionarySettingsSheet` to `DictionarySettingsDialog` and converted it from a bottom sheet to a formal dialog.
- Redesigned the dictionary settings UI with a clearer distinction between AI and external app modes.
- Added a "Search" option to the external dictionary list that triggers a web search.
- Updated `ExternalDictionaryHelper` to include a package blocklist and support for generic web search intents.
- Simplified `PdfHelper` by removing Pro user checks for the "Dictionary" action.
- Updated icons for dictionary settings across the EPUB and PDF readers.
