feat(web): wire local-decky teardown to DELETE /deckies/{name}

The Fleet UI only showed TEARDOWN for swarm-pinned deckies (POST
/swarm/hosts/{uuid}/teardown). Local deckies had no delete control though
the API now exposes DELETE /deckies/{name}.

teardown() branches on swarm vs local; the card's two-step arm/CONFIRM
button renders for any admin, keyed td:${host_uuid ?? 'local'}:${name}.

decnet_web/src/components/DeckyFleet.tsx

@@ -113,8 +113,7 @@ const DeckyFleet: React.FC<FleetProps> = ({ searchQuery = '' }) => {
   // Two-step teardown: first click arms the button, second click within
   // 4s actually fires the POST. Keeps swarm hosts safe from misclicks.
   const handleTeardown = async (d: Decky) => {
-    if (!d.swarm) return;
-    const key = `td:${d.swarm.host_uuid}:${d.name}`;
+    const key = `td:${d.swarm?.host_uuid ?? 'local'}:${d.name}`;
     if (armed !== key) { arm(key); return; }
     setArmed(null);
     const r = await teardown(d);

decnet_web/src/components/DeckyFleet/DeckyCard.test.tsx

@@ -98,6 +98,19 @@ describe('DeckyCard', () => {
     expect(screen.getByText('CONFIRM')).toBeInTheDocument();
   });
 
+  it('shows TEARDOWN for admin on a local (non-swarm) decky, keyed td:local:', () => {
+    const local = makeDecky({ name: 'decoy-local' });
+    const { rerender } = render(
+      <DeckyCard {...baseProps} isAdmin decky={local} />,
+    );
+    expect(screen.getByText('TEARDOWN')).toBeInTheDocument();
+
+    rerender(
+      <DeckyCard {...baseProps} isAdmin armed="td:local:decoy-local" decky={local} />,
+    );
+    expect(screen.getByText('CONFIRM')).toBeInTheDocument();
+  });
+
   it('clicking the card body fires onInspect', async () => {
     const onInspect = vi.fn();
     const user = userEvent.setup();

decnet_web/src/components/DeckyFleet/DeckyCard.tsx

@@ -38,7 +38,7 @@ export const DeckyCard: React.FC<Props> = ({
   const hits = hitsFor(decky);
   const hot = dot === 'hot';
   const dotClass = mutating ? 'mutating' : dot;
-  const tdKey = decky.swarm ? `td:${decky.swarm.host_uuid}:${decky.name}` : '';
+  const tdKey = `td:${decky.swarm?.host_uuid ?? 'local'}:${decky.name}`;
 
   // Live service mutation is local-only (admin, non-swarm). Swarm
   // deckies live on a remote agent — the W3 path runs docker compose
@@ -347,12 +347,12 @@ export const DeckyCard: React.FC<Props> = ({
               {mutating ? 'MUTATING' : 'FORCE MUTATE'}
             </button>
           )}
-          {decky.swarm && isAdmin && (
+          {isAdmin && (
             <button
               className="btn alert small"
               disabled={tdBusy}
               onClick={() => onTeardown(decky)}
-              title="Stop this decky on its host"
+              title={decky.swarm ? 'Stop this decky on its host' : 'Tear down this decky'}
             >
               <PowerOff size={10} />
               {tdBusy

decnet_web/src/components/DeckyFleet/useDeckyFleet.ts

@@ -38,7 +38,7 @@ export interface UseDeckyFleetResult {
   mutate: (name: string) => Promise<MutateResult>;
   /** Update or clear a decky's periodic mutate interval. */
   setMutateInterval: (name: string, minutes: number | null) => Promise<boolean>;
-  /** Tear down a swarm-pinned decky on its host. */
+  /** Tear down a decky — swarm-pinned on its host, or local via DELETE. */
   teardown: (d: Decky) => Promise<TeardownResult>;
   /** Optimistically apply a server-returned services list to a card
    *  (used by DeckyCard's add/remove-service flow). */
@@ -171,10 +171,13 @@ export function useDeckyFleet(): UseDeckyFleetResult {
   );
 
   const teardown = useCallback(async (d: Decky): Promise<TeardownResult> => {
-    if (!d.swarm) return { ok: false, reason: 'not a swarm decky' };
     setTearingDown((prev) => new Set(prev).add(d.name));
     try {
-      await api.post(`/swarm/hosts/${d.swarm.host_uuid}/teardown`, { decky_id: d.name });
+      if (d.swarm) {
+        await api.post(`/swarm/hosts/${d.swarm.host_uuid}/teardown`, { decky_id: d.name });
+      } else {
+        await api.delete(`/deckies/${encodeURIComponent(d.name)}`);
+      }
       await fetchDeckies(deployMode?.mode);
       return { ok: true };
     } catch (err: unknown) {