[Go] [Breaking Change] `ai.ToolContext` should have type parameter for original input

[apascal07]

Describe the bug
ai.ToolContext has a field OriginalInput with type any; this type should actually be the input type of the tool. This is a debatable change though because some or even most tools won't have interrupts and as such ai.ToolContext.OriginalInput will not be used but all tools will nonetheless have to have a more unwieldy function signature. For tools that do use interrupts, you can get a strongly typed input with ai.OriginalInputAs[T].