test: add prose-fixture end-to-end smoke for kitchen view (task 0003)

Pull a reduced end-to-end smoke forward into the slice so the view flow
is exercised over a real on-disk recipe, not just a temp file.

Add fixtures/prose.md — a recipe using only this slice's modelled
constructs (frontmatter, headings, plain paragraphs) so it renders
losslessly. integration_test now runs `kitchen view fixtures/prose.md`
as a subprocess and asserts the frontmatter, separator, headings,
paragraphs, and flat document order end-to-end. smoke_test covers
`kitchen --help` exiting 0 with the view command listed.

The full fixtures/basic.md smoke remains task 0007, which needs 0004's
richer nodes before that fixture renders losslessly.

.claude/tasks/0003-view-skeleton.md

@@ -68,4 +68,12 @@ They assert real observable behaviour against independent literals rather than r
 ### Review follow-up applied
 
 The `runCli` and `stripAnsi` test helpers were extracted into `packages/bin/src/test-support.ts` to remove duplication the review flagged across the bin test files.
-The scaffold's remaining `test.todo` placeholders (future block/inline types, annotations, the smoke test) are left intact for their owning tasks.
+The scaffold's remaining `test.todo` placeholders (future block/inline types, annotations) are left intact for their owning tasks.
+
+### End-to-end coverage pulled forward
+
+A reduced end-to-end smoke was pulled forward so the vertical slice is validated the way a user runs it.
+`fixtures/prose.md` is a committed recipe using only the constructs this slice models — frontmatter, headings at levels 1–3, and plain-text paragraphs — so it renders losslessly today.
+`integration_test.ts` runs `kitchen view fixtures/prose.md` as a subprocess and asserts the ANSI-stripped output: exit 0, frontmatter YAML before the body, the separator, every heading and paragraph, and flat document order.
+`smoke_test.ts` covers `kitchen --help` exiting 0 with the `view` command listed.
+This is a subset of task 0007's smoke, which still owns the full `fixtures/basic.md` end-to-end once 0004's richer nodes make that fixture render losslessly.

fixtures/prose.md

@@ -0,0 +1,22 @@
+---
+title: Buttered Toast
+servings: 2
+tags: [breakfast, simple]
+---
+
+# Buttered Toast
+
+The simplest breakfast, and a good way to smoke-test the renderer.
+Everything here is plain prose — no lists, code, or annotations yet.
+
+## Method
+
+Toast the bread until golden on both sides.
+
+### Timing
+
+Spread the butter while the toast is still warm so it soaks in.
+
+## Serving
+
+Cut into triangles and serve at once.

packages/bin/src/integration_test.ts

@@ -1,33 +1,43 @@
 import { describe, expect, test } from "bun:test";
-import { mkdtempSync, rmSync, writeFileSync } from "node:fs";
-import { tmpdir } from "node:os";
 import { join } from "node:path";
 
 import { runCli, stripAnsi } from "./test-support.ts";
 
 const CLI = `${import.meta.dir}/index.ts`;
+const FIXTURE = join(import.meta.dir, "..", "..", "..", "fixtures", "prose.md");
 
 describe("cli — integration", () => {
-  test("invokes core parser and produces output for a real fixture file", async () => {
+  test("renders a real recipe fixture end-to-end", async () => {
-    const dir = mkdtempSync(join(tmpdir(), "kitchen-md-"));
+    const { exitCode, stdout } = await runCli(["view", FIXTURE], CLI);
-    const file = join(dir, "recipe.md");
-    writeFileSync(
-      file,
-      "---\ntitle: Test Recipe\nservings: 2\n---\n\n# Heading One\n\nA plain paragraph of prose.\n",
-    );
-
-    try {
-      const { exitCode, stdout } = await runCli(["view", file], CLI);
     const output = stripAnsi(stdout);
+    const lines = output.split("\n");
+    const lineOf = (needle: string): number => lines.findIndex((line) => line.includes(needle));
 
     expect(exitCode).toBe(0);
-      expect(output).toContain("title: Test Recipe");
+
+    expect(output).toContain("title: Buttered Toast");
     expect(output).toContain("servings: 2");
-      expect(output).toMatch(/─+/);
+    expect(output).toContain("tags:");
-      expect(output).toContain("Heading One");
+    expect(output).toContain("breakfast");
-      expect(output).toContain("A plain paragraph of prose.");
+    expect(output).toContain("simple");
-    } finally {
+
-      rmSync(dir, { recursive: true, force: true });
+    expect(lines.some((line) => /^─+$/.test(line))).toBe(true);
-    }
+
+    expect(output).toContain("Buttered Toast");
+    expect(output).toContain("Method");
+    expect(output).toContain("Timing");
+    expect(output).toContain("Serving");
+
+    expect(output).toContain("The simplest breakfast");
+    expect(output).toContain("Toast the bread until golden on both sides.");
+    expect(output).toContain("Spread the butter while the toast is still warm");
+    expect(output).toContain("Cut into triangles and serve at once.");
+
+    const separatorLine = lines.findIndex((line) => /^─+$/.test(line));
+    expect(lineOf("servings: 2")).toBeLessThan(separatorLine);
+    expect(separatorLine).toBeLessThan(lineOf("Method"));
+    expect(lineOf("Method")).toBeLessThan(lineOf("Timing"));
+    expect(lineOf("Timing")).toBeLessThan(lineOf("Serving"));
+    expect(lineOf("Method")).toBeLessThan(lineOf("Toast the bread until golden on both sides."));
   });
 });

packages/bin/src/smoke_test.ts

@@ -1,6 +1,13 @@
-import { describe, test } from "bun:test";
+import { describe, expect, test } from "bun:test";
+
+import { runCli } from "./test-support.ts";
 
 describe("smoke", () => {
-  test.todo("kitchen --help exits with code 0");
+  test("kitchen --help exits with code 0", async () => {
+    const { exitCode, stdout } = await runCli(["--help"], `${import.meta.dir}/index.ts`);
+
+    expect(exitCode).toBe(0);
+    expect(stdout).toMatch(/view/);
+  });
   test.todo("kitchen parse <fixture> outputs structured JSON covering all annotation types");
 });