Add `name` attribute to `@McpToolParam` for custom MCP tool argument names

Expected Behavior

@McpToolParam should support an optional name attribute to customize the external MCP tool argument name.

  @McpTool(name = "get_weather")
  public String getWeather(@McpToolParam(name = "city_name") String cityName) {
        return cityName;
  }

This should generate an input schema with city_name:

  {
    "type": "object",
    "properties": {
      "city_name": {
        "type": "string"
      }
    },
    "required": ["city_name"]
  }

A tool call using city_name should bind to the Java parameter cityName.

Current Behavior

mcp/mcp-annotations currently uses the Java reflection parameter name for top-level tool input schema properties
and runtime argument binding.

For example:

  @McpTool(name = "get_weather")
  public String getWeather(String cityName) {
        return cityName;
  }

generates and expects cityName.

There is no MCP-specific way to expose city_name while keeping the Java method parameter named cityName.

Context

I want to expose MCP tool arguments using an external naming style such as snake_case while keeping idiomatic Java
camelCase parameter names internally.

A possible API would be:

  public @interface McpToolParam {

        String name() default "";

        boolean required() default true;

        String description() default "";

  }

Since @McpToolParam already targets both PARAMETER and FIELD, the same name attribute could also be honored for
nested object properties in generated schemas.

Start in mcp/mcp-annotations by tracing @McpToolParam handling for top-level schema generation and runtime argument binding. Check how its PARAMETER and FIELD targets are processed, then verify behavior for the city_name example. Done means custom external names work for schema properties and bind back to Java parameters, including nested object properties.