fix: configure test typings and root database linting

tsconfig.eslint.json

@@ -0,0 +1,8 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "noEmit": true,
+    "types": ["jasmine"]
+  },
+  "include": ["src/**/*.ts", "db.ts"]
+}