**Fonts**
Dynamically load text and icon fonts when the device boots.
Font bitdepth depends on whether the device is an ESP32 one and whether it has external RAM available.
When no external RAM is available on ESP32, only small and medium font variants are generated; large font variants refer to the medium size ones.
Implemented Appearance settings app for changing font and font size.
**Other changes**
- Added keyboard shortcuts to delete or rename files in directory views.
- Improved app-grid tile sizing to provide more room for labels.
- Reduced the default LED strip brightness.
New features:
- SDK version 7.0.0 packages include version metadata and platform-specific application settings.
- Apps gain POSIX support for file polling, terminal attributes, and standard input/output, plus additional C and POSIX functions.
- Shell commands can launch installed headless apps using their registered app settings.
- Apps can exit with a status code, and terminal clear commands support clearing from the cursor to the end, from the start through the cursor, or the entire display.
Fixes:
- SDK integration builds locate the build tool reliably and use settings for the selected platform.
- ESP32 file operations handle invalid paths and existing directories more consistently.
