Create timer function to initialise card database from filesystem (#14)

- Create a new datasource for an in-memory sqlite database
- Create a setup function to initialise the card database

#13

Reviewed-on: https://gitea.vylpes.xyz/External/card-drop/pulls/14
Co-authored-by: Ethan Lane <ethan@vylpes.com>
Co-committed-by: Ethan Lane <ethan@vylpes.com>

src/constants/CardRarity.ts

@@ -0,0 +1,6 @@
+export enum CardRarity {
+    Bronze,
+    Silver,
+    Gold,
+    Legendary,
+}