fix: derive SERVER_VERSION from package.json

dbmole reported a hardcoded SERVER_VERSION of 0.1.0 while the package was
already published as 0.1.1: the constant had drifted because a bump has to
touch two places. Both servers now read the version from package.json
(resolveJsonModule + a JSON import attribute), so a release updates one
place and the reported version can no longer fall behind.

Add a dbmole guard test that add_connection publishes a non-empty
inputSchema with the expected required fields, mirroring esmole, so a future
`.superRefine` on the schema cannot silently empty it.

packages/esmole-mcp/src/server.ts

@@ -1,6 +1,7 @@
 import { registerConnectionTools } from '@dbmole/core'
 import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js'
 import * as z from 'zod'
+import pkg from '../package.json' with { type: 'json' }
 import type { EsBackend } from './es/backend.js'
 import { ping } from './esBackend.js'
 import { esFormatError } from './esError.js'
@@ -16,7 +17,7 @@ import {
 } from './schema.js'
 import { registerEsTools } from './tools/index.js'
 
-export const SERVER_VERSION = '0.1.1'
+export const SERVER_VERSION = pkg.version
 
 const patchSchema = z
     .object({