Merge develop into main (#327)

## New features
- Implemented support for app packaging in firmware and `tactility.py`: load `.app` files instead of `.elf` files. Install apps remotely or via `FileBrowser`.
- Ensure headless mode works: all services that require LVGL can deal with the absence of a display
- Service `onStart()` is now allowed to fail (return `bool` result)
- Added and improved various file-related helper functions

## Improvements
- Completely revamped the SystemInfo app UI
- Improved Calculator UI of internal and external variant
- Fix Chat UI and removed the emoji buttons for now
- Fix for toolbar bottom padding issue in all apps

## Fixes
- Fix for allowing recursive locking for certain SPI SD cards
& more

Tactility/Source/app/filebrowser/SupportedFiles.cpp

@@ -5,13 +5,8 @@ namespace tt::app::filebrowser {
 
 constexpr auto* TAG = "FileBrowser";
 
-bool isSupportedExecutableFile(const std::string& filename) {
-#ifdef ESP_PLATFORM
-    // Currently only the PNG library is built into Tactility
-    return filename.ends_with(".elf");
-#else
-    return false;
-#endif
+bool isSupportedAppFile(const std::string& filename) {
+    return filename.ends_with(".app");
 }
 
 bool isSupportedImageFile(const std::string& filename) {