Implement main application

[ArtemDychenko]

Key requirements:

File-based configuration

• Support for routes.txt, config.txt, lang.json files
• Error validation with on-screen message

User interface

• Support 4-button membrane keypad
• OLED display with list support (menu, route/direction selection)
• Navigation: up/down buttons, approve, undo
• Retention of last state after restart

IBIS functionality

• Sending telegrams: DS001, DS001neu, DS003, DS003a, DS003d, DS003c, DS3aMAS, DS009, DS3cneu
• Sent data: route number, direction (text and code), data for internal boards

Language and character encoding

• Multilingualism with character mapping in lang.json
• Support only ASCII 7-bit - missing characters replaced ?

Direction change and status overview

• Quick direction change without rerouting
• Status screen (after 3 sec hold 2+3): list of active telegrams, software version

Upgrade mode

• Hosting website for updating files