STM32F767ZI: FileX SD card logging integration

[alieissa-commits]

Description

Enable local storage logging to preserve data when the board is offline or disconnected from the network. The system will write CSV telemetry records using the FileX filesystem, starting with a RAM-backed drive and expanding to a physical SD Card.

• Integrate FileX Core: Add the FileX filesystem library source files to the CMake target.
• Implement RAM Disk Driver: Allocate a block of internal SRAM and write a FileX RAM Disk driver wrapper.
• Implement logger_thread:
  • Initialize FileX (fx_system_initialize).
  • Format and open the RAM disk media (fx_media_format, fx_media_open).
  • Create a local file telemetry.csv and write CSV headers.
  • Listen to the sensor Message Queue, format the readings as CSV rows, and write/flush them to the file.
• Configure SDMMC Hardware: Initialize the SDMMC1 peripheral in 4-bit wide bus mode and its associated GPIO pins in board_init.c.
• Implement Physical SD Card Logging:
  • Integrate the STM32 HAL SD driver into CMake.
  • Write the FileX SD Card block driver wrapper.
  • Configure the logger_thread to automatically check for a physical SD Card on boot. If present, mount and log to the SD Card; if missing, fall back seamlessly to the RAM Disk.