Add keyboard layout [Ru, Pl, Cz, Ua] for T-Deck and CardKB devices

[timurey]

Hey!
I've implemented the ability to change the keyboard layout for locales supported by Meshtastic fonts: RU, UA, PL, CZ.
It works on devices with CardKB and T-Desk, the keyboard shortcut for changing the layout is fn-L.

In addition to adding a layout change handler and a mapping table for various layouts, I've added code to support UTF-8 strings in the message input field.

I can't add support for other input devices, but I think this will be a good start for adding other layouts and expanding the supported input device types in different languages.

I only tested the firmware on devices with high resolutions (e-ink, T-Deck), but it should work well on OLED displays as well.

• I have tested that my proposed changes behave as described.
• I have tested that my proposed changes do not cause any obvious regressions on the following devices:
  • T-Deck
  • Heltec E213
  • Heltec E290
  • NRF52 Pro-micro DIY

[CLAassistant]

All committers have signed the CLA.

[fifieldt]

Thanks, this looks like a nice implementation.

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[jp-bennett]

I don't love that the character replacement logic is in cannedMessages. That module is already too much of a catch-all.

[timurey]

Great point, I completely agree. cannedMessages is indeed turning into a module that does too much. The character replacement logic for keyboard layouts is a separate responsibility.

My proposal: I'll move it out into a dedicated kbLayout.c/.h module, as you suggested.
It will expose a function, const char *applyCurrentLayout(char key) which cannedMessages can call.
Also I’ll move keyboard layouts mapping tables, so all layout-specific data will be encapsulated in the new module.
The current module will have a layout indicator and utf8 character processing functions

[timurey]

Sorry for messy commit history