Add Network + Bluetooth config in Web UI
- src/system/network.py: WiFi scan/connect/hotspot via nmcli + iwlist fallback
- src/system/bluetooth.py: BT scan/pair/connect/MIDI via bluetoothctl
- REST endpoints: /api/wifi/* and /api/bluetooth/* (16 endpoints)
- Web UI: tabbed settings with Network + Bluetooth panels
- network.js: WiFi scan, connect modal, saved nets, hotspot
- bluetooth.js: BT scan, pair/unpair, connect, MIDI service
- style.css: tabs, network list, BT device list, signal indicators
- scripts/setup-bt-midi.sh: BT MIDI systemd bridge service
- tests/test_network.py: 22 tests (nmcli/iwlist, fallback, hotspot)
- tests/test_bt.py: 24 tests (status, scan, pair, MIDI, edge cases)
- _gather_state includes wifi + bluetooth sub-objects
- All 93 tests pass
shawn
b4237f2f1d