fix(citizen-scripting-lua): Add fail condition on missing directory

[jag3dagster]

Applies to LuaIOPOpen and LuaIOReadDir

Goal of this PR

Update LuaIOPOpen and LuaIOReadDir to send an error state when no directory is found at the provided path.

How is this PR achieving the goal

Invert the existing logic checking for INVALID_DEVICE_HANDLE to instead indicate that we have discovered that the specified path doesn't exist.

This PR applies to the following area(s)

Server, ScRT: Lua

...

Successfully tested on

Game builds: ..

Platforms: Windows

Checklist

• Code compiles and has been tested successfully.
• Code explains itself well and/or is documented.
• My commit message explains what the changes do and what they are for.
• No extra compilation warnings are added by these changes.

Fixes issues