Harden Playwright server startup wait

Allow the Datasette subprocess more time to become reachable under CI load.

If startup still times out, terminate the process and include stdout and stderr in the assertion so future failures have useful diagnostics.

tests/test_playwright.py

@@ -17,7 +17,7 @@ def find_free_port():
         return sock.getsockname()[1]
 
 
-def wait_for_server(process, url, timeout=10):
+def wait_for_server(process, url, timeout=30):
     deadline = time.monotonic() + timeout
     last_error = None
     while time.monotonic() < deadline:
@@ -36,7 +36,20 @@ def wait_for_server(process, url, timeout=10):
         except httpx.HTTPError as ex:
             last_error = repr(ex)
         time.sleep(0.1)
-    raise AssertionError(f"Timed out waiting for {url}: {last_error}")
+    if process.poll() is None:
+        process.terminate()
+        try:
+            stdout, stderr = process.communicate(timeout=5)
+        except subprocess.TimeoutExpired:
+            process.kill()
+            stdout, stderr = process.communicate()
+    else:
+        stdout, stderr = process.communicate()
+    raise AssertionError(
+        f"Timed out waiting for {url}: {last_error}\n"
+        f"stdout:\n{stdout}\n"
+        f"stderr:\n{stderr}"
+    )
 
 
 @pytest.fixture
@@ -1113,10 +1126,7 @@ def test_insert_row_flow_uses_custom_column_field(page, datasette_server):
     assert "title" in preview_text
     assert "metadata" in preview_text
     assert "From CSV" in preview_text
-    assert (
-        dialog.locator(".row-edit-bulk-preview-auto").first.text_content()
-        == "auto"
-    )
+    assert dialog.locator(".row-edit-bulk-preview-auto").first.text_content() == "auto"
     assert "null" not in preview_text
     assert "undefined" not in preview_text
     preview_cell_style = dialog.locator(