launcher: add favorite apps

[eratoriele]

Favorite apps always appear above non-favorite apps
Accepts regex, same logic as #920
Added the same regex logic to hidden apps

This is what it looks like with the following config:

"favoriteApps": [
  "",
  "zen",
  "steam",
  "^.*Thunderbird.*$"
],
"hiddenApps": [
  "^.*cachyos.*$"
]

Since the regex logic is repeated in all 3 locations I created a new util function. However none of the current util files seem suitable for it. Let me know if there is a better place for this function

There didn't seem to be a formatting guideline for the c++ files so I tried to follow the rest of the file.

Should the favorite apps list be indexed? Currently they use the same frequency->name sorting. Should the launcher respect the order of the favoriteApps list in the config?

[soramanew]

For formatting the C++, use clang-format, there is a .clang-format file in the base of the repo so it should follow those rules.

For the sorting, I don't really mind either, though probably just keep it as sorting by frequency for consistency.

[Markus328]

I personally think keeping the order of list is bettet than any type of sorting. It would be probably a good idea to the user to set the most frequent apps at the top and doing this they can substitute the app very easily by another one with the same role.

Ex: the most used app is firefox, because is a browser. If the user changes to Zen, it can keep the "same shortcut" to open Zen instead of selecting manually until the Zen becomes the most used app and goes to top again

[eratoriele]

I also think giving the user some choice in the ordering might be useful. However I don't know if any other launcher has a custom ordering option. I have no idea if that is a conscious decision or just my ignorance

Also, I was getting the following warning:
WARN scene: @modules/launcher/items/AppItem.qml[79:-1]: TypeError: Cannot read property 'id' of null
when the command key was entered into the launcher, so i added a null check on the favoriteIcon's active prop