SD Class Implementation

[samuelnguyen999]

The SD class currently provides a partial interface for SD card operations. This issue tracks the work needed to fully implement and validate the SD storage functionality used across the device.

Goals

• Expand the SD class to include complete, reliable SD card interaction features.
• Review all methods defined in SD_TC (C++ implementation) and determine which should be included or updated.
• Confirm compatibility with the target hardware environment and the SdFat library.

Reference: SD_TC Public Operations (from header file)

writeToDataLog()
appendToLog()
countFiles()
exists()
format()
getRemoteLogContents()
listRootToBuffer()
mkdir()
open()
printRootDirectory()
remove()
todaysDataFileName()
writeToRemoteLog()

Internal/Private Helper Methods

- appendStringToPath()
- iterateOnFiles()
- updateRemoteFileSize()
- incrementFileCount()
- listFile()

Additional Items for Review & Refinement

• File-stack depth management (MAX_DEPTH)
• Buffer management for file listing and log retrieval
• Use of PROGMEM for remoteFileName
• Error-state tracking via hasHadError
• Proper singleton lifecycle management (instance() / deleteInstance())