refactor: align frontend with FSD architecture

steiger.config.ts

@@ -0,0 +1,20 @@
+import { defineConfig } from 'steiger'
+import fsd from '@feature-sliced/steiger-plugin'
+
+export default defineConfig([
+  ...fsd.configs.recommended,
+  {
+    ignores: [
+      './src/shared/api/generated-api/**',
+      './src/shared/model/generated-zod/**',
+      './src/shared/ui-kit/**',
+    ],
+  },
+  {
+    files: ['./src/entities/user/**'],
+    rules: {
+      // User is a domain entity even if the current app consumes it from one protected layout.
+      'fsd/insignificant-slice': 'off',
+    },
+  },
+])