[EGD-5748] Remake Cellular flow

This commit remakes cellular data flow
introducing full error propagation.

[EGD-6613] Audio assets tags are not displayed

When selecting ring/sms/notification sound the title from audio tags is
displayed. If tags are empty the filename is shown.

[EGD-5849] Make calculator compute previous operations

Modify calculator behavior according to PO input:
* Compute existing equation before entering next operation
* Limit digit input to 7 digits
* Start each number input from empty input

[EGD-6337] Add desktop tethering notification

This PR adds home screen tethering notification. The notifications
allows user to disconnect tethering from desktop by focusing on
the notification and pressing `KEY_ENTER`

This PR adds also home screen notifications icons in `.png` format.
Icons shall be converted to `.vpi` and used in other tasks regarding
home screen notifications.

[EGD-6574] Update image/user/db/sms_003.sql

Co-authored-by: Michał Kamoń
Co-authored-by: Piotr Tański

[EGD-6574] Create new SMS SQL

Working on nice SMS messages to be displayed by defualt.

[EGD-6612] Remove debug flags in audio

Debug flags introduced accidentally with EGD-6497.

Signed-off-by: Marcin Smoczyński <smoczynski.marcin@gmail.com>

[EGD-6497] Add audio transcoding framework

Add a mechanism to apply a data transform on the stream's input. An
example mono to stereo transform is provided.

Signed-off-by: Marcin Smoczyński <smoczynski.marcin@gmail.com>

[EGD-6519] Initialize settings database with factory data

Put factory values from personalization.json into settings db

[EGD-6521] Generating eeprom

Tool for generating eeprom image with factory data

[EGD-6457] Add power management for USB

When the USB is disconnected, we turn off the peripherals
by going into the suspend bus mode.

[EGD-6606] Fix the sound for meditation app

Added sound media as separate file, and changed path for it in code.

[EGD-6456] ListView based desktop notification

This PR provides following changes in notifications:
- notifications were extracted as widget for pop-up-based
locked-screen implementation
- notifications are ListView based implemented
- the most recent notification is displayed on the top of the list

[EGD-6513] Volume control feedback

Added volume control feedback during music playback over Bluetooth.
Changed volume buttons handler logic in service audio to use actions
instead of messages.

[EGD-6355] Adjust MuditaOS to be used with Secure Boot

The start address of the OS image adjusted to comply with HAB
Secure Boot. Proper SNVS initialization performed at system startup.
SNVS drivers updated to most recent version. Image signing can be
performed as a part of build process. See doc/secure_boot.md for
more info.

[EGD-5661] Add power management for filesystem

Add peripheral control (USDHC and PLL2 clocks)
for file system support.
This will save energy and extend battery life.

[EGD-6110] Cyclic db write

WAL option used, checkpoint set to 1

[EGD-5632] Remove "systemStarted" from "DeveloperMode" EndPoint

Remove `systemStarted` field as it's no longer used.

[EGD-6545] Enable magnetometer LPDCM mode

To be able to reduce the power usage of the phone, magnetometer
has been switched into interrupt driven LPDCM mode. Added some
fixups maintaining current behavior on startup and disabling
the tethering mode

[EGD-6344] Fix SystemView compilation

Add necessary FreeRTOS configurations to run SystemView