Add connection retries to ParadeDB test helper

PostgreSQL may not be ready to accept queries immediately after the TCP
port becomes reachable (Docker port forwarding opens the port before
PostgreSQL finishes initialization). Retry the connection to handle this
timing window.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: whummer

paradedb/tests/test_extension.py

@@ -1,3 +1,5 @@
+import time
+
 import boto3
 import psycopg2
 from localstack.utils.strings import short_uid
@@ -12,15 +14,21 @@
 DATABASE = "mydatabase"
 
 
-def get_connection():
-    """Create a connection to ParadeDB."""
-    return psycopg2.connect(
-        host=HOST,
-        port=PORT,
-        user=USER,
-        password=PASSWORD,
-        database=DATABASE,
-    )
+def get_connection(retries: int = 15, sleep: float = 2.0):
+    """Create a connection to ParadeDB, retrying until the server is ready."""
+    for attempt in range(retries):
+        try:
+            return psycopg2.connect(
+                host=HOST,
+                port=PORT,
+                user=USER,
+                password=PASSWORD,
+                database=DATABASE,
+            )
+        except psycopg2.OperationalError:
+            if attempt == retries - 1:
+                raise
+            time.sleep(sleep)
 
 
 def test_connect_to_paradedb():