* Furi: replace obsolete furiac_exit with osThreadExit, drop obsolete apis and test. Rename systemd to flipper and move to separate file, cleanup. ApiHal: Rename timebase to os and move freertos hooks there, move insomnia api to power module.
* Furi: new thread helper
* Furi: cleanup thread documentation
* Flipper, AppLoader: update to use FuriThread. Update tasks signatures to match FuriThreadCallback signature.
* F4: rename API_HAL_TIMEBASE_DEBUG to API_HAL_OS_DEBUG
* Applications: rename FuriApplication to FlipperApplication, use FuriThreadCallback signature for apps.
* C++ app template sample, new exit method
* SYSTEM: tickless mode with deep sleep.
* Move FreeRTOS ticks to lptim2.
* API: move all sumbodules init routines to one place.
* Timebase: working lptim2 at tick source.
* API Timebase: lp-timer routines, timer access safe zones prediction and synchronization.
* FreeRTOS: adjust configuration for tickless mode.
* NFC: support for tickless mode.
* API Timebase: improve tick error handling in IRQ.
* Apploader: use insomnia mode to run applications.
* BLE: prevent sleep while core2 starting.
* HAL: nap while in insomnia mode.
Co-authored-by: coreglitch <mail@s3f.ru>