UI: Create OBS Studio folder for default recording location

[Warchamp7]

Description

This updates the default directory for recordings to be a newly created OBS Studio folder inside the default directory %UserProfile%/Videos/OBS Studio on Windows /home/<User>/OBS Studio on Linux (?) /Users/<User>/Movies/OBS Studio on macOS (?)

Code for Linux and mac will need review and suggestions because I am completely guessing there and it will almost certainly not compile.

Motivation and Context

Better organization for users

How Has This Been Tested?

Tested on Windows.

Ensured the directory is created during initial startup and properly set for new Profiles.

Types of changes

• Tweak (non-breaking change to improve existing functionality)

Checklist:

• [x] My code has been run through clang-format.
• [x] I have read the contributing document.
• [x] My code is not on the master branch.
• [x] The code has been tested.
• [x] All commit messages are properly formatted and commits squashed where appropriate.
• [x] I have included updates to all appropriate documentation.