feat: add multi-dialect schema initialization

src/core/errors.ts

@@ -0,0 +1,13 @@
+export class IdentityDBError extends Error {
+  constructor(message: string) {
+    super(message);
+    this.name = 'IdentityDBError';
+  }
+}
+
+export class IdentityDBConfigurationError extends IdentityDBError {
+  constructor(message: string) {
+    super(message);
+    this.name = 'IdentityDBConfigurationError';
+  }
+}