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/examples/19-json.ts

@@ -0,0 +1,103 @@
+// JSON mode: stream one prompt's run as JSON lines, like `pi --mode json`. Two modes:
+//   --events (default): the experimental agent events of watchEvents(), starting with a `snapshot` event.
+//   --ops: the raw ConversationView frames, starting with the view itself; each later line holds one commit's ops.
+// --storage sqlite (default) | jsonl | memory: sqlite writes a temporary database file, jsonl a temporary directory;
+// neither is deleted, and the path is printed to stderr at the end.
+// Uses OpenAI when OPENAI_API_KEY is set, and a scripted faux model otherwise.
+// Run from packages/durable:
+//   node --conditions=source --experimental-strip-types test/examples/19-json.ts --events "What is in this directory?"
+import { mkdtemp } from "node:fs/promises";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { BACKGROUND_CONTEXT } from "@earendil-works/chord/context";
+import { createModels } from "@earendil-works/pi-ai/models";
+import { fauxAssistantMessage, fauxProvider, fauxText, fauxToolCall } from "@earendil-works/pi-ai/providers/faux";
+import { openaiProvider } from "@earendil-works/pi-ai/providers/openai";
+import { NodeExecutionEnv } from "../../src/env/node.ts";
+import {
+	createRegistry,
+	defineExtension,
+	Harness,
+	MemoryStorage,
+	type Storage,
+	section,
+	watchEvents,
+} from "../../src/index.ts";
+import { openNodeJsonlStorage } from "../../src/storage/jsonl/node.ts";
+import { openNodeSqliteStorage } from "../../src/storage/sqlite/node.ts";
+import { createBashTool, createReadTool } from "../../src/tools/index.ts";
+
+const context = BACKGROUND_CONTEXT;
+const args = process.argv.slice(2);
+const mode = args.includes("--ops") ? "ops" : "events";
+const storageIndex = args.indexOf("--storage");
+const storageKind = storageIndex < 0 ? "sqlite" : args[storageIndex + 1];
+const prompt =
+	args.find((arg, index) => !arg.startsWith("--") && (storageIndex < 0 || index !== storageIndex + 1)) ??
+	"What is in this directory?";
+
+let storage: Storage;
+let location: string | undefined;
+if (storageKind === "sqlite") {
+	location = join(tmpdir(), `pi-durable-json-${Date.now()}.sqlite`);
+	storage = await openNodeSqliteStorage(location);
+} else if (storageKind === "jsonl") {
+	location = await mkdtemp(join(tmpdir(), "pi-durable-json-"));
+	storage = await openNodeJsonlStorage(location, context);
+} else if (storageKind === "memory") {
+	storage = new MemoryStorage();
+} else {
+	throw new Error(`Unknown --storage ${storageKind}; use sqlite, jsonl, or memory`);
+}
+const print = (value: unknown): void => void process.stdout.write(`${JSON.stringify(value)}\n`);
+
+const models = createModels();
+let model = { provider: "openai", modelId: "gpt-6-sol" };
+if (process.env.OPENAI_API_KEY !== undefined) {
+	models.setProvider(openaiProvider());
+} else {
+	const faux = fauxProvider({ tokensPerSecond: 200 });
+	models.setProvider(faux.provider);
+	model = { provider: "faux", modelId: "faux-1" };
+	faux.setResponses([
+		fauxAssistantMessage([fauxToolCall("bash", { command: "ls" }, { id: "call-1" })], { stopReason: "toolUse" }),
+		fauxAssistantMessage([fauxText("This directory holds the durable package sources, tests, and docs.")]),
+	]);
+}
+
+const registry = createRegistry();
+registry.install(
+	defineExtension({
+		name: "coding",
+		tools: [createReadTool(), createBashTool()],
+		sections: [section("preamble", () => "You are a concise coding assistant.", { tag: false })],
+	}),
+);
+const env = new NodeExecutionEnv({ cwd: process.cwd() });
+const harness = await Harness.open(storage, { models, registry, env: () => env }, context);
+const root = await harness.root(context, { agent: { model } });
+
+// Attach before submitting, so the stream covers the whole run.
+let stop: () => Promise<unknown>;
+if (mode === "events") {
+	const stream = await watchEvents(harness, root.id, context);
+	print(stream.snapshot);
+	stream.start(async (events) => {
+		for (const event of events) print(event);
+	});
+	stop = () => stream.stop();
+} else {
+	const watch = await root.watch(context);
+	print({ view: watch.value });
+	watch.start(async (_value, ops) => print({ ops }));
+	stop = () => watch.stop();
+}
+
+const submission = await root.submit({ type: "input", content: prompt }, context);
+await submission.wait(context);
+await harness.waitForIdle(context);
+// Let the last batch reach the listener before stopping.
+await new Promise((resolve) => setTimeout(resolve, 0));
+await stop();
+await harness.close(context);
+if (location !== undefined) console.error(`${storageKind} storage: ${location}`);