- Add subnet scanning for printer discovery in Docker environments

- Detect Docker environment automatically via /.dockerenv and cgroup
  - Show subnet input field in Add Printer dialog when running in Docker
  - Scan IP range for Bambu printer ports (8883 MQTT, 990 FTPS)
  - Query SSDP to get printer name/serial/model from discovered IPs
  - Map raw SSDP model codes to friendly names (BL-P001→X1C, O1D→H2D)

docker-compose.yml

@@ -2,11 +2,15 @@ services:
   bambuddy:
     build: .
     container_name: bambuddy
-    # OPTIONAL: Host network mode can help if you have camera or printer
-    # discovery issues. Docker's default bridge networking works in most setups.
-    # network_mode: host  # Uncomment this and remove "ports:" below if needed
-    ports:
-      - "8000:8000"
+    # Network mode options:
+    # - Default (bridge): Works for basic usage, but printer discovery and
+    #   camera streaming may not work since container can't reach LAN directly.
+    # - Host mode: Required for printer discovery scanning and camera streaming.
+    #   Uncomment "network_mode: host" and remove "ports:" section below.
+    #
+    network_mode: host
+    #ports:
+    #  - "8000:8000"
     volumes:
       - bambuddy_data:/app/data
       - bambuddy_logs:/app/logs