Allow EXPLAIN ANALYZE for SELECT queries when in restricted mode

[sargue]

Currently, it seems the validator doesn't allow it.

[02/12/26 10:59:51] INFO     Processing request of type            server.py:534
                             CallToolRequest
                    ERROR    Error executing query: Error          server.py:401
                             validating query: EXPLAIN (ANALYZE,
                             BUFFERS) SELECT chats.chat_id,
                             chats.creator, chats.other_user
                             FROM chats
                             JOIN users AS creator_user ON
                             chats.creator = creator_user.id
                             JOIN users AS other_user ON
                             chats.other_user = other_user.id
                             WHERE chats.chat_type = (SELECT
                             'ONE_ON_ONE'::chat_type)
                               AND (chats.creator =
                             '63ec322b-4a93-4d7a-aea8-7cdb3259e4b8
                             '
                                 OR chats.other_user =
                             '63ec322b-4a93-4d7a-aea8-7cdb3259e4b8
                             ')
                               AND creator_user.deletion_time = 0
                               AND other_user.deletion_time = 0

I stumbled upon this while using the MCP server from Claude Code, using Opus 4.6