refactor: initial moves

shared/lib/errors.ts

@@ -0,0 +1,18 @@
+export class ApplicationError extends Error {
+    constructor(message: string) {
+        super(message);
+        this.name = this.constructor.name;
+    }
+}
+
+export class UserError extends ApplicationError {
+    constructor(message: string) {
+        super(message);
+    }
+}
+
+export class SystemError extends ApplicationError {
+    constructor(message: string) {
+        super(message);
+    }
+}