Support BGR565 format

## Format Details
- **Type:** BGR (reversed RGB)
- **Description:** 16-bit BGR, 5-6-5 bit allocation
- **Color Depth:** 5 bits blue, 6 bits green, 5 bits red

## Implementation Requirements
- Parse BGR565 packed data from camera stream
- Handle reversed color order compared to RGB565
- Convert to display format if needed

## Parent Issue
Part of #1