Add BLE parser test vectors for BTHome, ATC/PVVX, Xiaomi, and Inkbird

[tigerbryan]

Add reproducible parser fixtures for common BLE advertisement payloads.\n\nUseful examples:\n- BTHome v2 temperature/humidity/battery\n- ATC/PVVX unencrypted payloads\n- Inkbird IBS-TH2 and IBS-TH2 Plus\n- Xiaomi stock encrypted placeholder cases