Fix test assertion: expect @-prefixed file path instead of file contents

The createPullRequest implementation correctly passes `@${input.bodyFile}`
as the --description argument (using Azure CLI's @file convention). The test
was incorrectly asserting against the file contents instead of the @-prefixed
path string that actually appears in the args array.

Author: cursoragent

apps/server/src/sourceControl/AzureDevOpsCli.test.ts

@@ -197,7 +197,7 @@ describe("AzureDevOpsCli.layer", () => {
         expect.objectContaining({
           command: "az",
           cwd: "/repo",
-          args: expect.arrayContaining(["--description", "Generated body"]),
+          args: expect.arrayContaining(["--description", `@${bodyFile}`]),
         }),
       );
       expect(mockRun.mock.calls[0]?.[0].args).not.toContain("--output");