* **New Features**
* Added a standalone LVGL module and enabled LVGL support in the simulator for richer local UI testing.
* **Refactor**
* HAL and LVGL split into distinct modules; startup and device attach/detach flows reorganized for clearer lifecycle management.
* Public APIs tightened with clearer nullability/documentation.
* **Bug Fixes**
* More consistent LVGL start/stop and device attach/detach behavior for improved stability.
## App state
Improved app state management in `LoaderService` and `GuiService`:
- Re-ordered some of the state transitions
- Hardened `GuiService` for repeated events (that might trigger a re-render of an app that's already rendered)
- Validate state transitions in `LoaderService` and crash if an app transitions from the wrong state to the next one.
## LoaderService
- Removed `tt::loader::` functions and expose `LoaderService` interface publicly.
- Implement `stopAll()` and `stopAll(id)` which stops all instances of an app, including any apps that were launched by it.
- Rename `stop()` functions to `stopTop()`
- Created `stopTop(id)` which only stops the top-most app when the app id matches.
- Moved `loader::LoaderEvent` to `loader::LoaderService::Event`
- Changed app instance `std::stack` to `std::vector`
## Improvements
- `ElfApp`: error 22 now shows a hint that `main()` might be missing
- Starting, installing and uninstalling apps now stops any running app (and its children) on the stack
## Bugfixes
- `HttpdReq` out of memory issue now shows an error message and doesn't crash anymore (this would happen on devices without PSRAM with WiFi active, when an app was installed)
- `GuiService::hideApp()` lock should not wait for timeout and now waits indefinitely
- `Buildscript/release-sdk-current.sh` deletes the previous local release before building a new one
## Code correctness
- App classes were made `final`
- Apps that had a `void start()` now have a `LaunchId start()`
- `tt::app::State`: renamed `Started` to `Created` and `Stopped` to `Destroyed` to properly reflect earlier name changes
## 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
- Implemented `LaunchId` to keep track of the apps that are started
- Implemented `FileSelection` app to select existing and/or new files.
- Moved some re-usable file functionality to `tt::file::`
- Renamed `Files` app to `FileBrowser`
- Updated `Notes` app to use new `FileSelection` functionality, and cleaned it up a bit.
- General code cleanliness improvements
- Create `Include/` folder for all main projects
- Fix some issues here and there (found while moving things)
- All includes are now in `Tactility/` subfolder and must be included with that prefix. This fixes issues with clashing POSIX headers (e.g. `<semaphore.h>` versus Tactility's `Semaphore.h`)
- Remove custom `ESP_TARGET` and use `ESP_PLATFORM` everywhere
- Add `Loader` service functionality to `tt::app::` namespace
- Make `Loader` `PubSub` usable by exposing the messages
- Add board type to crash log
- Don't show SD card in Files app when it's not mounted
- Set default SPI frequency for SD cards
- Move TT_VERSION to scope that works for sim too
- Log Tactility version and board on boot
- Rename "Yellow Board" to "CYD 2432S024C"
Ken Van Hoeylandt