Add Filter button and indicator that list is filtered

[SamHasler]

It would be useful to be able to filter by trigger words, so I could e.g. see all @audit-issue or @todo's without all the other bookmarks for other trigger words.

[tintinweb]

Hey @SamHasler,

is this different from #14 (comment)?

command -> inline bookmarks: set view filter: a regex that matches your filter (also matches the tag words)

[SamHasler]

Ah, hadn't realised that command existed. I was going by the available buttons on the panel.

I guess it would have been helpful if there was a button for it, but having the command is ok for now.

What's really needed is some indication in the UI that the list has been filtered. (I leave my machine on for days so I could come back and not realise it's been filtered at the moment.)

Could we change this issue to be for adding UI to indicate that the current list is filtered, and how. Or close it and I'll raise a separate issue for it if you like.

[tintinweb]

Added a couple more quick actions.

What's really needed is some indication in the UI that the list has been filtered. (I leave my machine on for days so I could come back and not realise it's been filtered at the moment.)

Haven't yet found an easy way to indicate if a filter is active (cannot change the image of the menu button at runtime and there is no generic way to represent an "active"/"pressed" menu button with the vscode API :/). Can only partially address this so far by adding the new set of buttons.