Write a SpacetimeDB backend module in TypeScript that defines five empty reducers with different argument patterns.

REDUCERS
- emptyReducerNoArgs: no arguments
- emptyReducerWithInt: count:number (i32)
- emptyReducerWithString: name:string
- emptyReducerWithTwoArgs: count:number (i32), name:string
- emptyReducerWithThreeArgs: active:boolean, ratio:number (f32), label:string
