feat(library): add source chips to game library

Chips show only when the user has 2 or more sources.
A selected source the user lacks stays visible, so it can be cleared.

public/i18n/en.json

@@ -256,6 +256,8 @@
     }
   },
   "LIBRARY": {
+    "SOURCE_LABEL": "Source",
+    "SOURCE": { "STEAM": "Steam", "PSN": "PlayStation", "MANUAL": "Manual" },
     "TITLE": "Game Library",
     "LOADING": "Loading games …",
     "EMPTY": "No games yet. Sync your Steam library or add a game.",