feat: convert ssh tunnels into a plugin

src/ui/sidebar/HostExportDialog.tsx

@@ -27,7 +27,7 @@ const GROUPS: { key: FieldGroup; label: string }[] = [
   { key: "connection", label: "groupConnection" },
   { key: "notes", label: "groupNotes" },
   { key: "tags", label: "groupTags" },
-  { key: "tunnels", label: "groupTunnels" },
+  { key: "proxy", label: "groupProxy" },
   { key: "jumpHosts", label: "groupJumpHosts" },
   { key: "quickActions", label: "groupQuickActions" },
   { key: "featureFlags", label: "groupFeatureFlags" },
@@ -38,7 +38,7 @@ const DEFAULT_GROUPS: FieldGroup[] = [
   "connection",
   "notes",
   "tags",
-  "tunnels",
+  "proxy",
   "jumpHosts",
   "quickActions",
   "featureFlags",