fix(maestro): draft-pane regressions from the integration review

Six findings from reviewing the accumulated blitz/spawn-v2 diff:

- loadRecents restored the seeded cwd but never emitted it, so the leaf's
  draft kept cwd:"" and the next render reseeded the form blank.
- stripDrafts did not recurse, so every half-filled draft in a split tab
  was written to localStorage; the old test passed only because hydrate
  discards draft on the way back in.
- showRawCwd and selectPreset grabbed focus from async init paths, so a
  draft pane stole the caret seconds after mounting.
- .mv-draft inherited no layout once the form left .modal-body.
- onSuccess mounted the new session onto a leaf that may have been closed
  while the POST was in flight, stranding it in no pane.

web/src/persistence.test.ts

@@ -99,4 +99,30 @@ describe("serializeLayout", () => {
     }
     expect(leaves(restored!.tabs[0].root).map((l) => l.sessionId)).toEqual(["s1", null]);
   });
+
+  it("keeps the draft out of the stored blob itself, not just out of hydrate", () => {
+    // A draft pane only exists once a tab has split, so the strip has to walk
+    // into split branches; asserting on the restored layout alone passes even
+    // when the draft was written to localStorage, because hydrate drops it.
+    const layout = hydrate({
+      tabs: [
+        {
+          id: "t",
+          root: {
+            kind: "split",
+            dir: "row",
+            a: { kind: "leaf", id: "l1", sessionId: "s1" },
+            b: { kind: "leaf", id: "l2", sessionId: null },
+          },
+        },
+      ],
+      activeTabId: "t",
+    }) as Layout;
+    const draftLeaf = leaves(layout.tabs[0].root).find((l) => !l.sessionId)!;
+    draftLeaf.draft = { command: "claude", cwd: "/home/user/secret-project", name: "amber-fox" };
+
+    const raw = serializeLayout(layout);
+    expect(raw).not.toContain("secret-project");
+    expect(raw).not.toContain("amber-fox");
+  });
 });