invalid-server-variable
@typespec/openapi3/invalid-server-variableSeverity: error
This diagnostic is issued when a variable in the @server decorator is not defined as a string type.
Since server variables are substituted into the server URL which is a string, all variables must have string values.
To fix this issue, make sure all server variables are of a type that is assignable to string.
Example
Section titled โExampleโ@server("{protocol}://{host}/api/{version}", "Custom endpoint", { protocol: "http" | "https", host: string, version: 1, // Should be a string: "1"})