Implement secret clipboard entry conventions

[42Willow]

keepassxreboot/keepassxc#10233 (comment)

Code snippet from keepassxc

    mime->setData("x-kde-passwordManagerHint", QByteArrayLiteral("secret"));

[42Willow]

May be related to #58 or may be only an issue with my setup

[sentriz]

I think you would need some option for wl-paste --watch to achieve this. something like "if x-kde-xxx is available as a mime option then don't do anything"

this is still a bit of a hack think

@bugaevc has also mentioned ideally we could have Wayland extensions to that keepass could set a "clipboard state" metadata that wl-paste would be able to ignore sensitive stuff. or pass the metadata in to cliphist so that it can ignore it

[bugaevc]

Related: bugaevc/wl-clipboard#177

[sentriz]

closing re #93