feat(S-102): Test-drive and implement --timeout flag, config layering, and default in

tools/ai-cli-dispatch/tests/config.test.ts

@@ -135,4 +135,71 @@ describe("resolveConfig", () => {
     });
     assert.strictEqual(config.defaultClient, undefined);
   });
+
+  it("returns default timeout of 600000 when no sources are present", () => {
+    const config = resolveConfig({
+      existsSync: () => false,
+      whichSync: () => undefined,
+    });
+    assert.strictEqual(config.timeout, 600_000);
+  });
+
+  it("loads timeout from file config", () => {
+    const config = resolveConfig({
+      existsSync: () => true,
+      readFileSync: () => JSON.stringify({ timeout: 120_000 }),
+      whichSync: () => undefined,
+    });
+    assert.strictEqual(config.timeout, 120_000);
+  });
+
+  it("overrides file timeout with env var", () => {
+    const config = resolveConfig({
+      env: { AI_CLI_TIMEOUT: "240000" },
+      existsSync: () => true,
+      readFileSync: () => JSON.stringify({ timeout: 120_000 }),
+      whichSync: () => undefined,
+    });
+    assert.strictEqual(config.timeout, 240_000);
+  });
+
+  it("overrides env timeout with CLI flag", () => {
+    const config = resolveConfig({
+      flags: { timeout: "480000" },
+      env: { AI_CLI_TIMEOUT: "240000" },
+      existsSync: () => true,
+      readFileSync: () => JSON.stringify({ timeout: 120_000 }),
+      whichSync: () => undefined,
+    });
+    assert.strictEqual(config.timeout, 480_000);
+  });
+
+  it("respects full priority ordering for timeout: flag > env > file > default", () => {
+    const config = resolveConfig({
+      flags: { timeout: "480000" },
+      env: { AI_CLI_TIMEOUT: "240000" },
+      existsSync: () => true,
+      readFileSync: () => JSON.stringify({ timeout: 120_000 }),
+      whichSync: () => undefined,
+    });
+    assert.strictEqual(config.timeout, 480_000);
+  });
+
+  it("ignores invalid timeout from env var and falls back to default", () => {
+    const config = resolveConfig({
+      env: { AI_CLI_TIMEOUT: "not-a-number" },
+      existsSync: () => false,
+      whichSync: () => undefined,
+    });
+    assert.strictEqual(config.timeout, 600_000);
+  });
+
+  it("ignores invalid timeout from file and falls back to default", () => {
+    const config = resolveConfig({
+      existsSync: () => true,
+      readFileSync: () => JSON.stringify({ timeout: "not-a-number" }),
+      whichSync: () => undefined,
+    });
+    assert.strictEqual(config.timeout, 600_000);
+  });
 });