chore(vendor): import pi 1.3.0

Imported as a linear vendor commit so forge rebases do not replay the upstream root tree.

git-subtree-dir: third_party/pi

git-subtree-split: 71023aec1546d6d677a65669c5665c0927ce0dd0

third_party/pi/packages/durable/test/memory-storage.test.ts

@@ -0,0 +1,32 @@
+import { BACKGROUND_CONTEXT } from "@earendil-works/chord/context";
+import { registerStorageConformance } from "@earendil-works/pi-durable/testing";
+import { describe, expect, it } from "vitest";
+import { idFromNumber, seqFromNumber } from "../src/ids.ts";
+import { MemoryStorage } from "../src/storage/memory.ts";
+import { type EntryId, ROOT_CONVERSATION_ID } from "../src/types.ts";
+
+registerStorageConformance({ describe, expect, it }, "MemoryStorage", (use) => use(new MemoryStorage()));
+
+it("does not expose retained state through a prepared commit", async () => {
+	const storage = new MemoryStorage();
+	await storage.commit([{ type: "conversation", value: { id: ROOT_CONVERSATION_ID } }], BACKGROUND_CONTEXT);
+	const entryId = idFromNumber<EntryId>(2);
+	const prepared = storage.prepareCommit([
+		{
+			type: "entry",
+			value: {
+				id: entryId,
+				conversationId: ROOT_CONVERSATION_ID,
+				kind: "test",
+				data: { nested: [1] },
+			},
+		},
+	]);
+	const exposed = prepared.writes[0];
+	if (exposed.type !== "entry") throw new Error("Expected an entry write");
+	expect(() => (exposed.value.data as { nested: number[] }).nested.push(2)).toThrow();
+
+	expect(prepared.apply()).toBe(seqFromNumber(2));
+	expect(prepared.apply()).toBe(seqFromNumber(2));
+	expect((await storage.entry(entryId, BACKGROUND_CONTEXT))?.entry.data).toEqual({ nested: [1] });
+});