feat: expand discovery with systemd services, LXC/VMs, SSH terminal, and filebrowser

- Add systemd service discovery to backend
- Add Proxmox LXC/VM detection
- Add hostType field to config for better host categorization
- Fix SSH trust between hosts (ubuntu/grizzley -> truenas/proxmox)
- Add SSH terminal support via xterm.js
- Add filebrowser for browsing host filesystems
- Update frontend types and components for new node types

server/routes/discover.ts

@@ -0,0 +1,169 @@
+/**
+ * SSH Discovery API Endpoint
+ * 
+ * POST /api/discover - Discover all hosts via SSH and return their status
+ */
+
+import { Router } from 'express';
+import { execSync } from 'child_process';
+import { homedir } from 'os';
+import { getHostConfigs } from '../config';
+import { DiscoveryResponse } from '../types';
+
+const router = Router();
+
+interface HostDiscoveryResult {
+  name: string;
+  ip: string;
+  online: boolean;
+  containers?: string[];
+  services?: string[];
+  vms?: Array<{ id: string; name: string; status: string; type: 'lxc' | 'qemu' }>;
+  error?: string;
+}
+
+async function discoverHost(
+  name: string,
+  ip: string,
+  sshUser: string,
+  sshKeyPath?: string,
+  sshPort?: number,
+  hostType?: string
+): Promise<HostDiscoveryResult> {
+  try {
+    const keyPath = (sshKeyPath || `${homedir()}/.ssh/id_ed25519`).replace(/^~/, homedir());
+    console.error(`DEBUG: ${name} keyPath=${keyPath}, user=${sshUser}`);
+    const keyArg = `-i ${keyPath}`;
+    const portArg = sshPort && sshPort !== 22 ? `-p ${sshPort}` : '';
+    
+    const dockerCmd = `ssh -o ConnectTimeout=5 -o StrictHostKeyChecking=no ${keyArg} ${portArg} ${sshUser}@${ip} "docker ps --format '{{.Names}}'" 2>/dev/null`;
+    const dockerOutput = execSync(dockerCmd, { encoding: 'utf-8', timeout: 15000 });
+    const containers = dockerOutput.trim().split('\n').filter(c => c.trim());
+    
+    let services: string[] = [];
+    if (hostType !== 'proxmox') {
+      try {
+        const systemdCmd = `ssh -o ConnectTimeout=5 -o StrictHostKeyChecking=no ${keyArg} ${portArg} ${sshUser}@${ip} "systemctl list-units --type=service --state=running --no-pager --no-legend --quiet | awk '{print \\$1}'" 2>/dev/null`;
+        const systemdOutput = execSync(systemdCmd, { encoding: 'utf-8', timeout: 10000 });
+        services = systemdOutput.trim().split('\n').filter(s => s.trim());
+      } catch {
+        console.error(`DEBUG: ${name} systemd discovery failed`);
+      }
+    }
+    
+    let vms: Array<{ id: string; name: string; status: string; type: 'lxc' | 'qemu' }> = [];
+    if (hostType === 'proxmox' || name === 'proxmox') {
+      try {
+        const lxcCmd = `ssh -o ConnectTimeout=5 -o StrictHostKeyChecking=no ${keyArg} ${portArg} ${sshUser}@${ip} "pct list" 2>/dev/null`;
+        const lxcOutput = execSync(lxcCmd, { encoding: 'utf-8', timeout: 10000 });
+        const lxcLines = lxcOutput.trim().split('\n').slice(1);
+        for (const line of lxcLines) {
+          const parts = line.trim().split(/\s+/);
+          if (parts.length >= 2) {
+            vms.push({ id: parts[0], name: parts[1], status: parts[2] || 'unknown', type: 'lxc' });
+          }
+        }
+        
+        const vmCmd = `ssh -o ConnectTimeout=5 -o StrictHostKeyChecking=no ${keyArg} ${portArg} ${sshUser}@${ip} "qm list" 2>/dev/null`;
+        const vmOutput = execSync(vmCmd, { encoding: 'utf-8', timeout: 10000 });
+        const vmLines = vmOutput.trim().split('\n').slice(1);
+        for (const line of vmLines) {
+          const parts = line.trim().split(/\s+/);
+          if (parts.length >= 2) {
+            vms.push({ id: parts[0], name: parts[1], status: parts[2] || 'unknown', type: 'qemu' });
+          }
+        }
+      } catch {
+        console.error(`DEBUG: ${name} Proxmox discovery failed`);
+      }
+    }
+    
+    return {
+      name,
+      ip,
+      online: true,
+      containers,
+      services: services.length > 0 ? services : undefined,
+      vms: vms.length > 0 ? vms : undefined,
+    };
+  } catch (error: any) {
+    return {
+      name,
+      ip,
+      online: false,
+      containers: [],
+      error: error.message || 'Discovery failed',
+    };
+  }
+}
+
+// POST /api/discover - Discover all hosts via SSH
+router.post('/discover', async (req, res) => {
+  try {
+    const hosts = getHostConfigs();
+    
+    if (hosts.length === 0) {
+      const response: DiscoveryResponse = {
+        hosts: [],
+        timestamp: new Date().toISOString(),
+        errors: ['No hosts configured'],
+      };
+      return res.json(response);
+    }
+
+    const results: HostDiscoveryResult[] = [];
+    for (const host of hosts) {
+      try {
+        const keyPath = host.sshKeyPath?.replace(/^~/, homedir());
+        const result = await discoverHost(
+          host.name,
+          host.ip,
+          host.sshUser,
+          keyPath,
+          host.sshPort,
+          host.hostType
+        );
+        results.push(result);
+      } catch (error: any) {
+        results.push({
+          name: host.name,
+          ip: host.ip,
+          online: false,
+          containers: [],
+          error: error.message || 'Discovery failed'
+        });
+      }
+    }
+    
+    const errors: string[] = [];
+    results.forEach((result: HostDiscoveryResult) => {
+      if (!result.online && result.error) {
+        errors.push(`${result.name}: ${result.error}`);
+      }
+    });
+
+    const response: DiscoveryResponse = {
+      hosts: results.map(r => ({
+        name: r.name,
+        ip: r.ip,
+        online: r.online,
+        containers: r.containers,
+        services: r.services,
+        vms: r.vms,
+      })),
+      timestamp: new Date().toISOString(),
+      errors,
+    };
+
+    res.json(response);
+  } catch (error: any) {
+    const response: DiscoveryResponse = {
+      hosts: [],
+      timestamp: new Date().toISOString(),
+      errors: [error.message || 'Discovery failed'],
+    };
+    res.status(500).json(response);
+  }
+});
+
+export default router;