add .env and gitignore

.env.example

@@ -0,0 +1,16 @@
+# NetBox connection
+NETBOX_URL=https://netbox.example.com/
+NETBOX_TOKEN=your_token_here
+SSL_VERIFY=false
+
+# Scan configuration
+# SCAN_SOURCE: env | netbox | mixed
+SCAN_SOURCE=env
+NETWORKS=192.168.85.0/24,192.168.86.0/24
+
+# Filter NetBox prefixes by status when SCAN_SOURCE=netbox or mixed
+# Options: active, reserved, deprecated, container (leave empty for all)
+NETBOX_PREFIX_STATUS=active
+
+# NetBox tenant name to assign to discovered IPs
+TENANT=Your Tenant Name