Decal Placer + add new decals for mapping (#6548)

* abomination

* okay its less unabashedly garbage now

* other UI changes

* its britney bitch

* proper greyscale full/half/quarter tiles

* misc cleanup

* rsi

* Add a palette system. It's Kara's problem now.

* oops

* a

* Departmental palette alpha tweaks

* oopy

* so true

* Update Content.Shared/Decals/ColorPalettePrototype.cs

Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>

* fixes for that

* neutral light color and new warning lines

* dirt

* checkerboards

* oop

Co-authored-by: moonheart08 <moonheart08@users.noreply.github.com>
Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>

Resources/Locale/en-US/escape-menu/ui/options-menu.ftl

@@ -112,6 +112,7 @@ ui-options-function-open-abilities-menu = Open action menu
 ui-options-function-open-entity-spawn-window = Open entity spawn menu
 ui-options-function-open-sandbox-window = Open sandbox menu
 ui-options-function-open-tile-spawn-window = Open tile spawn menu
+ui-options-function-open-decal-spawn-window = Open decal spawn menu
 ui-options-function-open-admin-menu = Open admin menu
 
 ui-options-function-take-screenshot = Take screenshot