feat: add temp package to preferred manifest

[gameroman]

Closes #339

[43081j]

given its the same replacements as tempy, we should probably just have one document.

do not update the title of the tempy doc, just add a description before the replacements list like "creating temporary files and directories can now be achieved natively in modern engines, making libraries like tempy redundant.".

[gameroman]

Should I then instead of diffs make it examples without diffs or should I keep the diffs for tempy?

[43081j]

either works. whichever you think is most helpful.

in this case i dont have a preference since a diff will still be helpful, but so will a plain usage example.

sorry for the non-answer 😄