change: change log-query string value to bool

BREAKING CHANGE

As discussed on https://github.com/PostgREST/postgrest/issues/3934#issuecomment-3362806777,
this changes log-query to use a bool value, this:

- Simplifies config for users.
- Reduces effort in testing the different combinations.

Closes #3934

docs/references/configuration.rst

@@ -714,23 +714,14 @@ log-query
 ---------
 
   =============== =================================
-  **Type**        String
-  **Default**     "disabled"
+  **Type**        Boolean
+  **Default**     False
   **Reloadable**  Y
   **Environment** PGRST_LOG_QUERY
   **In-Database** `n/a`
   =============== =================================
 
-  Logs the SQL query for the corresponding request at the current :ref:`log-level`.
-  See :ref:`sql_query_logs`.
-
-    .. code:: bash
-
-        # Logs the main SQL query
-        log-query = "main-query"
-
-        # Disables logging the SQL query
-        log-query = "disabled"
+  Logs the SQL query for the corresponding request at the current :ref:`log-level`. See :ref:`sql_query_logs`.
 
 .. _openapi-mode:
 

docs/references/observability.rst

@@ -52,14 +52,12 @@ For diagnostic information about the server itself, PostgREST logs to ``stderr``
 SQL Query Logs
 --------------
 
-To log the :ref:`main SQL query <main_query>` executed for a request, set the :ref:`log-query` to ``main-query``.
-It will be logged based on the current :ref:`log-level` setting.
-For example, with this configuration:
+To log the SQL queries executed for a request, set the :ref:`log-query` to ``true``. It will be logged based on the current :ref:`log-level` setting.
 
 .. code-block:: bash
 
   log-level = "warn"
-  log-query = "main-query"
+  log-query = "true"
 
 The SQL queries will only be logged on ``400`` HTTP errors and up.
 So, if the user requests a resource without sufficient privileges: