Fix 21 bugs: build failures, broken pages, IPC mismatches, and missing error handling

Critical fixes:
- Add esbuild dependency and fix Vite build target (safari13 → es2022)
- Fix StorageDetail always failing (null node parameter)
- Fix VNC/Terminal console stuck on 'Connecting...' (add onConnected callback)
- Fix Ctrl+Alt+Del not working (add data-vnc attribute and event listener)
- Add serde(rename_all='camelCase') to all 27 Rust structs crossing IPC
- Fix login methods returning empty connection_id (generate from URL hash)
- Fix add_connection not storing connections in HashMap
- Fix keyring_entry panicking on failure (replace expect with map_err)

High-severity fixes:
- Fix refresh_ticket reading wrong keyring entry for username
- Add onError handlers to all 23 mutations (toast notifications)
- Fix stale closure on activeConnectionId (use getState() instead)
- Fix WebSocket listener teardown race condition
- Add WebSocket reconnection retry limit (max 10 attempts)

Medium-severity fixes:
- Add Settings navigation to CommandPalette (Cmd+K)
- Disable dead Nodes/Containers sidebar items
- Wire up HardwareTab save button with warning toast
- Wire up QuickActions navigation buttons
- Add Dashboard error state (was stuck on 'Loading...')
- Add default case to App.tsx view switch
- Extract formatBytes/formatUptime/formatNetworkRate to shared utility
- Fix formatBytes negative input bug

32 files changed, 1073 insertions(+), 356 deletions(-)

src/components/dashboard/NodeHealthGrid.tsx

@@ -3,27 +3,13 @@ import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card'
 import { Cpu, MemoryStick, HardDrive, Clock, Server, Box } from 'lucide-react'
 import { AreaChart, Area, ResponsiveContainer } from 'recharts'
 import type { ProxmoxNode, ProxmoxVM } from '@/types/proxmox'
+import { formatBytes, formatUptime } from '@/lib/format'
 
 interface NodeHealthGridProps {
   nodes: ProxmoxNode[] | undefined
   vms: ProxmoxVM[] | undefined
 }
 
-function formatUptime(seconds: number): string {
-  const days = Math.floor(seconds / 86400)
-  const hours = Math.floor((seconds % 86400) / 3600)
-  if (days > 0) return `${days}d ${hours}h`
-  return `${hours}h`
-}
-
-function formatBytes(bytes: number): string {
-  if (bytes === 0) return '0 B'
-  const k = 1024
-  const sizes = ['B', 'KB', 'MB', 'GB', 'TB']
-  const i = Math.floor(Math.log(bytes) / Math.log(k))
-  return `${(bytes / Math.pow(k, i)).toFixed(1)} ${sizes[i]}`
-}
-
 function getStatusColor(status: 'online' | 'offline'): string {
   return status === 'online' ? 'bg-green-500' : 'bg-red-500'
 }