refactor(frontend): modularize i18n architecture

frontend/src/router/guards/__tests__/homeGuard.spec.ts

@@ -0,0 +1,53 @@
+import { beforeEach, describe, expect, it } from 'vitest'
+import type { RouteLocationNormalized } from 'vue-router'
+
+import { resolveHomeRedirect } from '@/router/guards/homeGuard'
+
+function route(path: string, query: Record<string, string> = {}): RouteLocationNormalized {
+  return {
+    path,
+    fullPath: path,
+    query,
+    hash: '',
+    name: undefined,
+    params: {},
+    matched: [],
+    meta: {},
+    redirectedFrom: undefined,
+  } as RouteLocationNormalized
+}
+
+function authStore(options: { isAuthenticated: boolean; canAccessAdmin?: boolean }) {
+  return {
+    isAuthenticated: options.isAuthenticated,
+    canAccessAdmin: options.canAccessAdmin ?? false,
+  } as never
+}
+
+describe('resolveHomeRedirect', () => {
+  beforeEach(() => {
+    sessionStorage.clear()
+  })
+
+  it('ignores non-home routes and unauthenticated home visits', () => {
+    expect(resolveHomeRedirect(route('/dashboard'), route('/'), authStore({ isAuthenticated: true }))).toBeNull()
+    expect(resolveHomeRedirect(route('/'), route('/login'), authStore({ isAuthenticated: false }))).toBeNull()
+  })
+
+  it('allows authenticated users to return to the public home from the app shell', () => {
+    expect(resolveHomeRedirect(route('/'), route('/dashboard'), authStore({ isAuthenticated: true }))).toBe('')
+    expect(resolveHomeRedirect(route('/', { returnTo: '/guide' }), route('/external'), authStore({ isAuthenticated: true }))).toBe('')
+  })
+
+  it('consumes stored redirect path before falling back to dashboard defaults', () => {
+    sessionStorage.setItem('redirectPath', '/dashboard/api-keys')
+
+    expect(resolveHomeRedirect(route('/'), route('/external'), authStore({ isAuthenticated: true }))).toBe('/dashboard/api-keys')
+    expect(sessionStorage.getItem('redirectPath')).toBeNull()
+  })
+
+  it('routes authenticated users to the correct dashboard by role', () => {
+    expect(resolveHomeRedirect(route('/'), route('/external'), authStore({ isAuthenticated: true }))).toBe('/dashboard')
+    expect(resolveHomeRedirect(route('/'), route('/external'), authStore({ isAuthenticated: true, canAccessAdmin: true }))).toBe('/admin/dashboard')
+  })
+})