Add one-command install script and stability fixes

- Add install.sh for automated setup
- Add all component files (wrapper, service, config, verify)
- Add stability fixes section (WiFi PowerSave disable + Watchdog)
- Update README with new installation instructions

darkice.cfg.example

@@ -0,0 +1,20 @@
+[general]
+duration        = 0
+bufferSecs      = 2           # USB stability
+reconnect       = yes
+
+[input]
+device          = plughw:0,0  # USB card 0 (fixed by modprobe)
+sampleRate      = 44100
+bitsPerSample   = 16
+channel         = 2
+
+[icecast2-0]
+bitrateMode     = cbr
+format          = mp3
+bitrate         = 320
+server          = localhost
+port            = 8000
+password        = hackme       # ← CHANGE to your Icecast source password
+mountPoint      = rapi.mp3     # Sonos URL: http://pi-ip:8000/rapi.mp3
+name            = Record Player