fix(clipboard): correct clipboard when used through SSH or WSL

[jboillot]

Hello,

First, sorry for the PR #18 that was buggy. When I noticed it, I put it in draft, but I should have written a clearer message!

This PR has been tested and it works both on WSL and through SSH. Here are some insights:

• Previously, the arboard clipboard was always initialized, which caused errors on WSL and SSH sessions. Now, it is initialized lazily and as a last resort.
• I discovered it was necessary to provide piped stdout and stderr output channels to the child process clip.exe on WSL otherwise the command fails.
• The way to set the clipboard through SSH uses an ANSI sequence (OSC52) that is not supported by all terminals (for example, not GNOME Terminal). However, I guess it is still better than nothing!

[Brooooooklyn]

@jboillot nevermind, thanks!