fix: correct types of `map` variables, and set default TLS min age check to 30s (to match the README)

Remove the type map from the map variables (module inputs) as it is incorrect. Most of the variables should accept elements with different types, and therefore should not be of type map. Instead, define the types in detail which also provides more precise type-checking.

Clarify defaults for TLS checking and authentication proxy options in the README.

Closes #17 (closed)