feat(maestro): hang draft state off layout leaves, never persisted (#57)

web/src/layout.ts

@@ -11,8 +11,23 @@ import type { Uuid } from "./types.js";
 
 export type Dir = "row" | "col";
 
+/** Half-filled spawn-form state for a draft pane (issue #57): an empty leaf
+ *  renders the spawn form instead of a placeholder, and each pane's values
+ *  hang off its own leaf so two drafts stay independent. Never persisted —
+ *  a reload gives back an empty form (persistence strips it). */
+export interface Draft {
+  command: string;
+  cwd: string;
+  name: string;
+  worktreeEnabled?: boolean;
+  worktreeBranch?: string;
+  worktreeCleanup?: boolean;
+  /** Whether the cwd lives in the raw text input (vs a picked recent row). */
+  cwdRawVisible?: boolean;
+}
+
 export type Node =
-  | { kind: "leaf"; id: string; sessionId: Uuid | null }
+  | { kind: "leaf"; id: string; sessionId: Uuid | null; draft?: Draft | null }
   | { kind: "split"; dir: Dir; a: Node; b: Node; ratio: number };
 
 export type Leaf = Extract<Node, { kind: "leaf" }>;
@@ -89,7 +104,7 @@ export function splitLeaf(
   dir: Dir,
   after: boolean,
 ): string {
-  const fresh: Leaf = { kind: "leaf", id: freshId("l"), sessionId };
+  const fresh: Leaf = { kind: "leaf", id: freshId("l"), sessionId, draft: null };
   const rec = (n: Node): Node => {
     if (n.kind === "leaf") {
       if (n.id !== targetId) return n;

web/src/persistence.test.ts

@@ -1,7 +1,7 @@
 import { describe, expect, it } from "vitest";
 
-import { hydrate } from "./persistence.js";
-import { leaves } from "./layout.js";
+import { hydrate, serializeLayout } from "./persistence.js";
+import { leaves, type Layout } from "./layout.js";
 
 describe("hydrate", () => {
   it("rejects anything that is not a tab-bearing object", () => {
@@ -61,4 +61,42 @@ describe("hydrate", () => {
     });
     expect(leaves(layout!.tabs[0].root).map((l) => l.sessionId)).toEqual(["s"]);
   });
+
+  it("never restores draft state, even if a stale blob carries it", () => {
+    const layout = hydrate({
+      tabs: [
+        { id: "t", root: { kind: "leaf", id: "l1", sessionId: null, draft: { command: "zsh", cwd: "/x" } } },
+      ],
+      activeTabId: "t",
+    });
+    expect(leaves(layout!.tabs[0].root)[0]).not.toHaveProperty("draft");
+  });
+});
+
+describe("serializeLayout", () => {
+  it("strips draft state so a reload gives back an empty form", () => {
+    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/project", name: "amber-fox" };
+
+    const restored = hydrate(JSON.parse(serializeLayout(layout)).layout);
+    expect(restored).not.toBeNull();
+    for (const leaf of leaves(restored!.tabs[0].root)) {
+      expect(leaf.draft ?? null).toBeNull();
+    }
+    expect(leaves(restored!.tabs[0].root).map((l) => l.sessionId)).toEqual(["s1", null]);
+  });
 });

web/src/persistence.ts

@@ -14,12 +14,30 @@ const VERSION = 1;
 
 export function saveLayout(layout: Layout): void {
   try {
-    localStorage.setItem(KEY, JSON.stringify({ v: VERSION, layout }));
+    localStorage.setItem(KEY, serializeLayout(layout));
   } catch {
     // Storage full or unavailable (private mode) — persistence is best-effort.
   }
 }
 
+/** Serialise the layout for storage with draft state stripped (issue #57): a
+ *  reload gives back an empty form, never a stale half-filled one. */
+export function serializeLayout(layout: Layout): string {
+  const clean: Layout = {
+    ...layout,
+    tabs: layout.tabs.map((t) => ({
+      ...t,
+      root: stripDrafts(t.root),
+    })),
+  };
+  return JSON.stringify({ v: VERSION, layout: clean });
+}
+
+function stripDrafts(node: Node | null): Node | null {
+  if (!node || node.kind !== "leaf") return node;
+  return { ...node, draft: null };
+}
+
 export function loadLayout(): Layout | null {
   let raw: string | null;
   try {