vcxsrv: Add .xlaunch file associations script

[lluccia]

Adds .xlaunch file associations scripts on vcxsrv installer.

The registry keys were obtained from the vcxsrv installer script source code (https://sourceforge.net/p/vcxsrv/code/ci/master/tree/xorg-server/installer/vcxsrv-64.nsi#l166), and adapted to user context using vscode manifest and reg scripts as references.

[lluccia]

/verify

[StarsbySea]

/verify

[github-actions[bot]]

All changes look good.

Wait for review from human collaborators.

vcxsrv

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