chore: snapshot working tree - pty_exited notifications + in-flight inference WIP

feat(booterm): structured pty_exited WS notifications. Plan-validated, impl-validated, code-reviewed green (contracts build clean, contracts test 29/29, booterm + web typecheck clean).

wip: in-progress inference/provider refactor (agents.ts, provider.ts, new llama-providers.ts, removed llama-args-validator), plus arena, dispatcher, compaction, schema changes.

openspec: pty-exit-notifications complete; x-agent-flags planned (not yet implemented).

apps/web/src/components/control/FleetTab.tsx

@@ -0,0 +1,51 @@
+import { useState } from 'react';
+import { AnimatePresence } from 'framer-motion';
+import { Settings2 } from 'lucide-react';
+import { ControlFleetHost } from '@/hooks/useControlStream';
+import { HostCard } from './HostCard';
+import { HostConfigEditor } from './HostConfigEditor';
+
+export interface GpuData {
+  vram_used: number;
+  vram_total: number;
+  temperature: number;
+  power: number;
+}
+
+interface FleetTabProps {
+  hosts: ControlFleetHost[];
+  gpuMap: Map<string, GpuData>;
+}
+
+export function FleetTab({ hosts, gpuMap }: FleetTabProps) {
+  const [editing, setEditing] = useState<string | null>(null);
+
+  if (hosts.length === 0) {
+    return (
+      <div className="flex items-center justify-center h-full">
+        <p className="text-sm text-muted-foreground">No hosts connected</p>
+      </div>
+    );
+  }
+
+  return (
+    <div className="flex-1 overflow-y-auto p-4 space-y-4">
+      <AnimatePresence mode="popLayout">
+        {hosts.map((host) => (
+          <div key={host.providerId} className="relative">
+            <button
+              type="button"
+              onClick={() => setEditing(host.providerId)}
+              title="SSH config editor"
+              className="absolute top-2 right-2 z-10 p-1.5 rounded-md text-muted-foreground hover:text-foreground hover:bg-muted/40"
+            >
+              <Settings2 className="size-4" />
+            </button>
+            <HostCard host={host} gpuData={gpuMap.get(host.providerId) ?? null} />
+          </div>
+        ))}
+      </AnimatePresence>
+      {editing && <HostConfigEditor providerId={editing} onClose={() => setEditing(null)} />}
+    </div>
+  );
+}