fix: no loopback return listener when the browser is not on this machine

runCheckout started its 127.0.0.1 listener and handed Stripe its return URLs
whenever the terminal could wait, including with --no-browser and inside SSH
sessions. In both cases the browser runs elsewhere, so after paying the user
landed on a connection-refused page for a port on the wrong machine; the
terminal still recovered by polling the plan, but the landing was wrong.

--no-browser now means what it says and SSH_CONNECTION / SSH_TTY / SSH_CLIENT
mean the same thing: no listener, no return URLs, Stripe returns to the
console billing page, and the plan poll is the only signal.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

Author: Justin Helmer

src/billing/checkout.ts

@@ -5,7 +5,7 @@ import { isApiError } from '../errors/api';
 import { CLIError } from '../errors/base';
 import { Spinner } from '../output/progress';
 import { openBrowser } from '../utils/browser';
-import { isInteractive } from '../utils/env';
+import { isInteractive, isRemoteTerminal } from '../utils/env';
 import type { BillingCycle, CatalogPlan, WorkspacePlan } from './plans';
 import { startReturnListener, type ReturnListener, type ReturnOutcome } from './return-listener';
 
@@ -95,7 +95,12 @@ function printCheckoutUrl(config: Config, url: string, noBrowser: boolean, deps:
 // the return URLs). Ctrl+C stops waiting and counts as "not now".
 export async function runCheckout(config: Config, opts: CheckoutOptions, deps: CheckoutDeps = defaultDeps): Promise<CheckoutOutcome> {
   const waits = deps.canWait(config);
-  const listener = waits ? await deps.startListener() : null;
+  // The loopback listener only helps when the browser runs on this machine.
+  // --no-browser says it does not, and an SSH session means it cannot; in
+  // both cases Stripe returns to the console page and the plan poll below
+  // is the only signal.
+  const browserIsHere = !opts.noBrowser && !isRemoteTerminal();
+  const listener = waits && browserIsHere ? await deps.startListener() : null;
   // Registered before the checkout request so a return that lands during it
   // is already visible when the wait starts.
   let returned: ReturnOutcome | null = null;

src/utils/env.ts

@@ -52,3 +52,9 @@ export function shouldUseColor(noColor: boolean): boolean {
   if (process.env.FORCE_COLOR) return true;
   return isStdoutTTY();
 }
+
+// A terminal reached over SSH cannot be the machine the browser runs on, so a
+// loopback listener there would never be reached by a redirect.
+export function isRemoteTerminal(env: NodeJS.ProcessEnv = process.env): boolean {
+  return Boolean(env.SSH_CONNECTION || env.SSH_TTY || env.SSH_CLIENT);
+}

test/billing-checkout.test.ts

@@ -231,12 +231,25 @@ describe('runCheckout', () => {
     assert.equal(h.out.join(''), 'file:///etc/passwd\n');
   });
 
-  it('honours --no-browser', async () => {
-    const h = harness();
-    const run = runCheckout(mockConfig({ output: 'text', nonInteractive: false }), { ...base, noBrowser: true }, h.deps);
-    h.listener!.settle('cancel');
-    await run;
+  it('honours --no-browser: nothing opened, no loopback listener, Stripe returns to the console', async () => {
+    const h = harness({ planIds: ['free', 'starter'] });
+    const outcome = await runCheckout(mockConfig({ output: 'text', nonInteractive: false }), { ...base, noBrowser: true }, h.deps);
+    assert.equal(outcome, 'upgraded');
     assert.deepEqual(h.opened, []);
+    assert.deepEqual(h.bodies, [{ workspaceId: 'ws_1', plan: 'starter', billingCycle: 'monthly' }]);
+  });
+
+  it('skips the loopback listener over SSH, where the browser is on another machine', async () => {
+    const prior = process.env.SSH_CONNECTION;
+    process.env.SSH_CONNECTION = '10.0.0.2 51000 10.0.0.1 22';
+    try {
+      const h = harness({ planIds: ['free', 'starter'] });
+      assert.equal(await runCheckout(mockConfig({ output: 'text', nonInteractive: false }), base, h.deps), 'upgraded');
+      assert.deepEqual(h.bodies, [{ workspaceId: 'ws_1', plan: 'starter', billingCycle: 'monthly' }]);
+    } finally {
+      if (prior === undefined) delete process.env.SSH_CONNECTION;
+      else process.env.SSH_CONNECTION = prior;
+    }
   });
 
   it('wraps a checkout API error, keeps its exit code, and always says how to upgrade later', async () => {