chore: Update ReadMe disclaimer (#13)

Co-authored-by: Wenxin Du <117315983+duwenxin99@users.noreply.github.com>

Author: averikitsch

README.md

@@ -1,7 +1,7 @@
 # Gemini CLI Extension - Cloud SQL for MySQL
 
 > [!NOTE]
-> This extension is currently in beta, and may see breaking changes until the first stable release (v1.0).
+> This extension is currently in beta (pre-v1.0), and may see breaking changes until the first stable release (v1.0).
 
 This Gemini CLI extension provides a set of tools to interact with [Cloud SQL for MySQL](https://cloud.google.com/sql/docs/mysql) instances. It allows you to manage your databases, execute queries, explore schemas, and troubleshoot issues directly from the [Gemini CLI](https://google-gemini.github.io/gemini-cli/), using natural language prompts.
 
@@ -43,7 +43,7 @@ Set the following environment variables before starting the Gemini CLI:
 * `CLOUD_SQL_MYSQL_PASSWORD`: The password for the database user.
 * `CLOUD_SQL_MYSQL_IP_TYPE`: (Optional) The IP type i.e. “Public” or “Private” (Default: Public).
 
-Ensure [Application Default Credentials](https://cloud.google.com/docs/authentication/gcloud) are available in your environment. 
+Ensure [Application Default Credentials](https://cloud.google.com/docs/authentication/gcloud) are available in your environment.
 
 > [!NOTE]
 > When using private IPs with Cloud SQL for MySQL, you must use a Virtual Private Cloud (VPC) network.
@@ -76,7 +76,7 @@ Interact with MySQL using natural language:
 *   **Data:**
     *  `list_tables`: Use this tool to list tables and descriptions.
     *  `execute_sql`: Use this tool to execute any SQL statement.
-    *  `get_query_plan`: Use this tool to generate an execution plan. 
+    *  `get_query_plan`: Use this tool to generate an execution plan.
     *  `list_active_queries`: Use this tool to lists top N (default 10) ongoing queries.
     *  `list_tables_missing_unique_indexes`: Use this tool to find tables that do not have primary or unique key constraint
     *  `list_table_fragmentation`: Use this tool to list fragmented tables