feat: WiFi access point setup script + README hotspot instructions

README.md

@@ -88,6 +88,25 @@ From any device on the same network:
 - **Browser:** http://pedal.local:8080
 - Or use the IP: http://192.168.x.x:8080
 
+### WiFi Hotspot (No Network? No Problem)
+
+If there's no WiFi network to join — stage, rehearsal space, park bench — the Pi can create its own:
+
+```bash
+# Run once to set up
+sudo bash scripts/setup-wifi-ap.sh
+
+# Or with custom SSID/password:
+sudo bash scripts/setup-wifi-ap.sh --ssid "Pi-Pedal" --psk "yourpassword"
+
+# Phone connects to "Pi-Pedal" → open http://pedal.local:8080
+
+# To turn it off and go back to client mode:
+sudo bash scripts/setup-wifi-ap.sh --disable
+```
+
+**Pro tip:** Add a USB WiFi dongle for dual-network — Pi creates hotspot on built-in WiFi, dongle handles internet access for git pulls and updates.
+
 ### 8. Wire It Up
 
 **Mono mode (standard pedal):**