Add UnitTests and made code testable with DI

TinfoilVibeServer/appsettings.json

@@ -7,16 +7,19 @@
   },
   "AllowedHosts": "*",
 
-  "RootDirectories": [ "\\\\NAS\\Roms\\Switch", "Z:\\imgs\\roms\\Switch" ],
-  "WhitelistExtensions": [ ".bin", ".jpg", ".png", ".txt" ],
-  "RomExtensions": [ ".xci", ".nsp", ".xcz" ],
-  "SnapshotFile": "index.tfl",
-  "SnapshotBackupFile": "snapshot.bin",
+  "KeySetFile": "prod.keys",
   "CredentialsFile": "credentials.json",
   "FingerprintsFile": "fingerprints.json",
   "BlacklistFile": "blacklist.json",
   "MaxFailedAttempts": 5,
-  "KeySetFile": "prod.keys",
+  "Snapshot" : {
+    "RootDirectories": [ "\\\\NAS\\Roms\\Switch", "Z:\\imgs\\roms\\Switch" ],
+    "WhitelistExtensions": [ ".bin", ".jpg", ".png", ".txt" ],
+    "RomExtensions": [ ".xci", ".nsp", ".xcz" ],
+    "CacheTtl": 60,
+    "SnapshotFile": "index.tfl",
+    "SnapshotBackupFile": "snapshot.bin"
+  },
   "TitleDb": {
     "CountryCode": "AU",
     "Language": "en",