Rename project references from Pixel View to ADS-Bit

Rename pixel-view.js to ads-bit.js, rename PixelADSB class to ADSBit,
and update all documentation and code comments to use ADS-Bit branding
consistently throughout the project.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

start.sh

@@ -1,4 +1,4 @@
 #!/bin/bash
 cd "$(dirname "$0")"
-echo "Starting Pixel View ADS-B server..."
+echo "Starting ADS-Bit server..."
 python3 server.py