188 sd card hot swap

[TobiasRoeddiger]

This PR adds support for hot swapping the microSD card. The first tests looks fine but will have to dig deeper.

[github-actions]

Build output available:
openearable_v2_firmware.elf.zip
openearable_v2_fota.zip

[TobiasRoeddiger]

Some test scenarios:

• Does it work if swithing between SD cards? Yes ✅
• Does it crash after longer time or remain stable? Works fine ✅
• What happens if the SD card is pulled out mid recording and reinserted or another card is inserted, does it still recover gracefully?
• Boot with no SD card inserted then insert and start. Works fine ✅
• Boot with SD card inserted, then remove and reinsert the same card and start recording. Works fine ✅
• Rapid repeated hot-swap. Works fine ✅
• Pull the card during right after starting recording.
• Pull the card during immediatley after ending recording
• Reinsert the same card after a mid-recording removal, then start a new recording.
• Insert a different card after a mid-recording removal, then start a new recording.
• Unsupported / damaged card.
• Full card / nearly full card. Ex
• Stress loop: record, stop, remove, insert, record again for many cycles.
• No-card idle after removal
• LED/state recovery checks. Expected: fault only when appropriate, and it returns to idle/ready once a valid card is back.