Test - Log file rotation and size limits

[brentru]

Objective: Verify log file size limits and file rotation for sd card logging mode work properly

Procedure:

1. Modify SD card capacity calculation (calculateFileLimits) to a smaller limit (500mb would take days, reduce it to simulate the capacity limit)
2. Remove all files off SD card to start fresh
3. Run device for extended period
4. Stop device, examine SD card

Expected Results:

• ✓ Max file size = 10% of usable SD capacity (accounting for 5% FAT
  overhead)
• ✓ Files don't exceed [predefined KB/MB size] capacity
• ✓ New files are created when limit reached (validate existing files are at the maximum file size)

Code Reference: ws_sdcard.cpp