feat: Add `getType()` support to **all** TS input bindings

[schloerke]

Ex handling of python value: https://github.com/posit-dev/py-shiny/blob/fcdc2d9efd69279556f405307308c4c7706a4110/shiny/input_handler.py#L169
Ex handling of R value: https://github.com/rstudio/shiny/blob/b56c275364c8a7e609274a61b775ef2e003f6399/R/server-input-handlers.R#L192

While the types wont necessarily always be leveraged, it is nice to have them available.