feat: Support `--reverse` for alt-tab

[bbb651]

Also fixes behavior of alt[-shift]-tab not triggering the first time when the launcher activates. This seems to have been done intentionally, but this does not match any existing implementation of window/tab switching I know (e.g. Gnome, KDE, Windows, MacOS, Firefox, Chromium, VSCode, Zed, etc.) and IMO is very bad UX because triggering it once quickly will do nothing windows are sorted by last window focus.

@git-f0x I worked on it some more and I think this is all that needs to be done on the cosmic-launcher side, but I haven't tried adding the alt-shift-tab shortcut yet.

Also, I ended up getting into a bit of a rabbit hole with debugging, to properly test the activation it has to run in cosmic-session, so I ended up symlinking it in-place of my system's cosmic-launcher, but then I had to resort to trying to write to a named pipe (which failed but I couldn't figure out why), and displaying it through the UI. Does cosmic-session provide a way to view logs for components for the current session, or is there any better way to test?