feat: add pr review (task 0013)

Add `pr review <n>` with the three action switches --approve,
--request-changes, and --comment, plus --body/--body-file. Exactly one
action flag is required; zero or multiple raise VALIDATION_ERROR before
any API call, mirroring the merge shorthand-conflict rule. Body
requirements are left to Gitea: a body-less event it rejects surfaces its
422 as VALIDATION_ERROR carrying the server's message. Output is
`review: { number, action }`.

test/pr-review.test.ts

@@ -0,0 +1,128 @@
+import { afterEach, describe, expect, it } from "vitest";
+import { startFixtureServer, type FixtureServer } from "./fixture-server.js";
+import { runCliTest, tempFiles, testModeEnv, type TempFiles } from "./harness.js";
+
+const REPO_PATH = "/api/v1/repos/testowner/testrepo";
+const REVIEWS_PATH = `${REPO_PATH}/pulls/9/reviews`;
+
+let server: FixtureServer;
+const files: TempFiles = tempFiles();
+
+afterEach(async () => {
+  await server.close();
+  files.cleanup();
+});
+
+function reviewPosted() {
+  return server.requests.find(
+    (request) => request.method === "POST" && request.path === REVIEWS_PATH,
+  );
+}
+
+describe("pr review", () => {
+  it("submits an APPROVED review and reports number and action for --approve", async () => {
+    server = await startFixtureServer([{ method: "POST", path: REVIEWS_PATH, body: {} }]);
+
+    const { stdout, exitCode } = await runCliTest(["pr", "review", "9", "--approve"], {
+      env: testModeEnv(server.url),
+    });
+
+    expect(exitCode).toBe(0);
+    expect(reviewPosted()?.body).toEqual({ event: "APPROVED" });
+    expect(stdout).toContain("review:");
+    expect(stdout).toContain("number: 9");
+    expect(stdout).toContain("action: approve");
+  });
+
+  it.each([
+    ["--request-changes", "REQUEST_CHANGES", "request-changes"],
+    ["--comment", "COMMENT", "comment"],
+  ])("submits %s as event %s and reports action %s", async (flag, event, action) => {
+    server = await startFixtureServer([{ method: "POST", path: REVIEWS_PATH, body: {} }]);
+
+    const { stdout, exitCode } = await runCliTest(["pr", "review", "9", flag], {
+      env: testModeEnv(server.url),
+    });
+
+    expect(exitCode).toBe(0);
+    expect(reviewPosted()?.body).toEqual({ event });
+    expect(stdout).toContain("review:");
+    expect(stdout).toContain("number: 9");
+    expect(stdout).toContain(`action: ${action}`);
+  });
+
+  it("rejects zero action flags before any API call", async () => {
+    server = await startFixtureServer([]);
+
+    const { stdout, exitCode } = await runCliTest(["pr", "review", "9"], {
+      env: testModeEnv(server.url),
+    });
+
+    expect(exitCode).toBe(2);
+    expect(stdout).toContain("code: VALIDATION_ERROR");
+    expect(server.requests).toHaveLength(0);
+  });
+
+  it.each([
+    ["--approve", "--comment"],
+    ["--approve", "--request-changes"],
+    ["--request-changes", "--comment"],
+  ])("rejects multiple action flags (%s %s) before any API call", async (...actions) => {
+    server = await startFixtureServer([]);
+
+    const { stdout, exitCode } = await runCliTest(["pr", "review", "9", ...actions], {
+      env: testModeEnv(server.url),
+    });
+
+    expect(exitCode).toBe(2);
+    expect(stdout).toContain("code: VALIDATION_ERROR");
+    expect(server.requests).toHaveLength(0);
+  });
+
+  it("surfaces a 422 from the server as VALIDATION_ERROR carrying its message", async () => {
+    server = await startFixtureServer([
+      {
+        method: "POST",
+        path: REVIEWS_PATH,
+        status: 422,
+        body: { message: "review body cannot be empty" },
+      },
+    ]);
+
+    const { stdout, exitCode } = await runCliTest(["pr", "review", "9", "--request-changes"], {
+      env: testModeEnv(server.url),
+    });
+
+    expect(exitCode).toBe(2);
+    expect(stdout).toContain("code: VALIDATION_ERROR");
+    expect(stdout).toContain("review body cannot be empty");
+  });
+
+  it("forwards a --body review body inline", async () => {
+    server = await startFixtureServer([{ method: "POST", path: REVIEWS_PATH, body: {} }]);
+
+    const { exitCode } = await runCliTest(
+      ["pr", "review", "9", "--comment", "--body", "Looks good"],
+      { env: testModeEnv(server.url) },
+    );
+
+    expect(exitCode).toBe(0);
+    expect(reviewPosted()?.body).toEqual({ event: "COMMENT", body: "Looks good" });
+  });
+
+  it("forwards a --body-file review body from the file contents", async () => {
+    server = await startFixtureServer([{ method: "POST", path: REVIEWS_PATH, body: {} }]);
+    const path = files.write("review.txt", "Please fix the tests");
+
+    const { exitCode } = await runCliTest(
+      ["pr", "review", "9", "--request-changes", "--body-file", path],
+      { env: testModeEnv(server.url) },
+    );
+
+    expect(exitCode).toBe(0);
+    expect(reviewPosted()?.body).toEqual({
+      event: "REQUEST_CHANGES",
+      body: "Please fix the tests",
+    });
+  });
+});