Update address output in headless mode (#8647)

## Describe your changes

Closes #8629

When Streamlit is started via `server.headless=true`, the address output
does not contain `localhost`, although the server can still be reached
via `localhost`. The `headless` mode just defines whether a browser is
started, not what the address binding is. So, the idea is to show
`localhost` also in case when `server.headless=true` is set.


## GitHub Issue Link (if applicable)

## Testing Plan

- Explanation of why no additional tests are needed
- Unit Tests (JS and/or Python)
- E2E Tests
- Any manual testing needed?

---

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lib/streamlit/web/bootstrap.py

@@ -250,15 +250,6 @@ def _print_url(is_running_hello: bool) -> None:
  ("Unix Socket", config.get_option("server.address")),
  ]
 
- elif config.get_option("server.headless"):
- internal_ip = net_util.get_internal_ip()
- if internal_ip:
- named_urls.append(("Network URL", server_util.get_url(internal_ip)))
-
- external_ip = net_util.get_external_ip()
- if external_ip:
- named_urls.append(("External URL", server_util.get_url(external_ip)))
-
  else:
  named_urls = [
  ("Local URL", server_util.get_url("localhost")),
@@ -268,6 +259,11 @@ def _print_url(is_running_hello: bool) -> None:
  if internal_ip:
  named_urls.append(("Network URL", server_util.get_url(internal_ip)))
 
+ if config.get_option("server.headless"):
+ external_ip = net_util.get_external_ip()
+ if external_ip:
+ named_urls.append(("External URL", server_util.get_url(external_ip)))
+
  cli_util.print_to_cli("")
  cli_util.print_to_cli(" %s" % title_message, fg="blue", bold=True)
  cli_util.print_to_cli("")

lib/tests/streamlit/web/bootstrap_test.py

@@ -151,6 +151,7 @@ def test_print_urls_remote(self, mock_get_internal_ip, mock_get_external_ip):
  bootstrap._print_url(False)
 
  out = sys.stdout.getvalue()
+ self.assertIn("Local URL: http://localhost", out)
  self.assertIn("Network URL: http://internal-ip", out)
  self.assertIn("External URL: http://external-ip", out)
 
@@ -175,6 +176,7 @@ def test_print_urls_remote_no_external(
  bootstrap._print_url(False)
 
  out = sys.stdout.getvalue()
+ self.assertIn("Local URL: http://localhost", out)
  self.assertIn("Network URL: http://internal-ip", out)
  self.assertNotIn("External URL: http://external-ip", out)
 
@@ -199,6 +201,7 @@ def test_print_urls_remote_no_internal(
  bootstrap._print_url(False)
 
  out = sys.stdout.getvalue()
+ self.assertIn("Local URL: http://localhost", out)
  self.assertNotIn("Network URL: http://internal-ip", out)
  self.assertIn("External URL: http://external-ip", out)