Add VLAN ID display and smart parent assignment for virtual interfaces

Agent changes:
- Parse /proc/net/vlan/config to extract VLAN IDs for interfaces
- Detect primary physical interface via default route
- Auto-assign primary interface as parent for virtual interfaces without explicit parent
- Added vlan_id field to NetworkInterfaceData

Dashboard changes:
- Display VLAN ID in format "interface (vlan X): IP"
- Show VLAN IDs for both nested and standalone virtual interfaces

This ensures virtual interfaces (docker0, tailscale0, etc.) are properly nested
under the primary physical NIC, and VLAN interfaces show their IDs.

Updated to version 0.1.170

agent/src/collectors/network.rs

@@ -49,10 +49,67 @@ impl NetworkCollector {
         }
     }
 
+    /// Get the primary physical interface (the one with default route)
+    fn get_primary_physical_interface() -> Option<String> {
+        match Command::new("ip").args(["route", "show", "default"]).output() {
+            Ok(output) if output.status.success() => {
+                let output_str = String::from_utf8_lossy(&output.stdout);
+                // Parse: "default via 192.168.1.1 dev eno1 ..."
+                for line in output_str.lines() {
+                    if line.starts_with("default") {
+                        if let Some(dev_pos) = line.find(" dev ") {
+                            let after_dev = &line[dev_pos + 5..];
+                            if let Some(space_pos) = after_dev.find(' ') {
+                                let interface = &after_dev[..space_pos];
+                                // Only return if it's a physical interface
+                                if Self::is_physical_interface(interface) {
+                                    return Some(interface.to_string());
+                                }
+                            } else {
+                                // No space after interface name (end of line)
+                                let interface = after_dev.trim();
+                                if Self::is_physical_interface(interface) {
+                                    return Some(interface.to_string());
+                                }
+                            }
+                        }
+                    }
+                }
+                None
+            }
+            _ => None,
+        }
+    }
+
+    /// Parse VLAN configuration from /proc/net/vlan/config
+    /// Returns a map of interface name -> VLAN ID
+    fn parse_vlan_config() -> std::collections::HashMap<String, u16> {
+        let mut vlan_map = std::collections::HashMap::new();
+
+        if let Ok(contents) = std::fs::read_to_string("/proc/net/vlan/config") {
+            for line in contents.lines().skip(2) {  // Skip header lines
+                let parts: Vec<&str> = line.split('|').collect();
+                if parts.len() >= 2 {
+                    let interface_name = parts[0].trim();
+                    let vlan_id_str = parts[1].trim();
+
+                    if let Ok(vlan_id) = vlan_id_str.parse::<u16>() {
+                        vlan_map.insert(interface_name.to_string(), vlan_id);
+                    }
+                }
+            }
+        }
+
+        vlan_map
+    }
+
     /// Collect network interfaces using ip command
     async fn collect_interfaces(&self) -> Vec<NetworkInterfaceData> {
         let mut interfaces = Vec::new();
 
+        // Parse VLAN configuration
+        let vlan_map = Self::parse_vlan_config();
+
         match Command::new("ip").args(["-j", "addr"]).output() {
             Ok(output) if output.status.success() => {
                 let json_str = String::from_utf8_lossy(&output.stdout);
@@ -113,6 +170,9 @@ impl NetworkCollector {
                                 Status::Unknown  // Virtual interfaces don't have meaningful link status
                             };
 
+                            // Look up VLAN ID from the map (use original name before @ parsing)
+                            let vlan_id = vlan_map.get(&name).copied();
+
                             interfaces.push(NetworkInterfaceData {
                                 name: interface_name,
                                 ipv4_addresses,
@@ -120,6 +180,7 @@ impl NetworkCollector {
                                 is_physical,
                                 link_status,
                                 parent_interface,
+                                vlan_id,
                             });
                         }
                     }
@@ -133,6 +194,17 @@ impl NetworkCollector {
             }
         }
 
+        // Assign primary physical interface as parent to virtual interfaces without explicit parent
+        let primary_interface = Self::get_primary_physical_interface();
+        if let Some(primary) = primary_interface {
+            for interface in interfaces.iter_mut() {
+                // Only assign parent to virtual interfaces that don't already have one
+                if !interface.is_physical && interface.parent_interface.is_none() {
+                    interface.parent_interface = Some(primary.clone());
+                }
+            }
+        }
+
         interfaces
     }
 }