Define a dedicated `vmvar_t` type for values stored in variable pages
and propagate it through interfaces that expose those values. Keep the
type as int for now so this commit does not change runtime behavior.
This separates VM storage from ordinary int buffers and makes a later
conversion to 16-bit storage mechanically checkable.
- nact.h and xsystem35.h no longer include scenario.h
- Removed `sys_*` aliases in nact.h
- sys_getString() and sys_getConstString() are moved to
scenario.c as sl_getString() and sl_getConstString()
- DEBUG_COMMAND macros are now defined in scenario.h
The second argument of DC command specifies the maximum index of the new
array. That means, `DC _,n,_:` allocates an array of size n+1 (a[0] to
a[n]).
This patch makes sure various D commands work with a[n], and a[n] is
correctly saved and loaded.
Now loadSysVar() does not shrink array variables using the data count in
the save file, so that files saved by old xsystem35 binary can be safely
loaded. This also matches the behavior of System3.9.
kichikuou