The only reason the getter existed was to check whether or not the
program NCA was null. Instead, we can just provide a function to query
for the existence of it, instead of exposing it entirely.
Neither of these functions require the use of shared ownership of the
returned pointer. This makes it more difficult to create reference
cycles with, and makes the interface more generic, as std::shared_ptr
instances can be created from a std::unique_ptr, but the vice-versa
isn't possible. This also alters relevant functions to take NCA
arguments by const reference rather than a const reference to a
std::shared_ptr. These functions don't alter the ownership of the memory
used by the NCA instance, so we can make the interface more generic by
not assuming anything about the type of smart pointer the NCA is
contained within and make it the caller's responsibility to ensure the
supplied NCA is valid.
A process should never require being reference counted in this
situation. If the handle to a process is freed before this function is
called, it's definitely a bug with our lifetime management, so we can
put the requirement in place for the API that the process must be a
valid instance.
Many of these aren't necessary and will cause this file to be required
to be recompiled whenever any changes to those files are made, which
lengthens compile times for no reason.
This also removes an unused metadata variable from AppLoader_XCI
