Add a "Copy as Markdown" button for the docs pages.

[smrdotgg]

Add a simple "Copy as Markdown" button next to the title for the docs pages.

I've gotten used to this feature on other docs sites and thought it'd be nice if sst had it.

demo.mp4

[vimtor]

implemented too in #6158

[rupokghosh]

This is a subtle yet excellent feature. I hope it gets merged!

[smrdotgg]

@vimtor, oh okay. If there's a different implementation that seems promising, I'm totally fine with closing this.

Hopefully though we get some solution out soon, because this is a super nice feature to have.

If the other PR is looking promising, feel free to close this PR.

Thanks for taking the time to look into this.

[vimtor]

@smrdotgg thanks!

i'm waiting for the other contributor's response. we might merge this soon if they don't reply.

even better, if you fork their changes, fix the bug and replace their button with yours, that would be ideal