feat(account): add forum login and sidebar account entry

src/global/authState.ts

@@ -0,0 +1,62 @@
+import { computed, ref } from "vue";
+
+import { setBackendToken } from "@/modules/backendApi";
+import type { AuthSession, SparkUser } from "./typedefinition";
+
+const AUTH_STORAGE_KEY = "spark-store-auth";
+
+const isSparkUser = (value: unknown): value is SparkUser => {
+  if (!value || typeof value !== "object" || Array.isArray(value)) return false;
+  const user = value as Record<string, unknown>;
+  return (
+    typeof user.id === "number" &&
+    typeof user.flarumUserId === "string" &&
+    typeof user.username === "string" &&
+    typeof user.displayName === "string" &&
+    typeof user.avatarUrl === "string" &&
+    typeof user.forumLevel === "string" &&
+    Array.isArray(user.forumGroups) &&
+    user.forumGroups.every((group) => typeof group === "string")
+  );
+};
+
+const isAuthSession = (value: unknown): value is AuthSession => {
+  if (!value || typeof value !== "object" || Array.isArray(value)) return false;
+  const session = value as Record<string, unknown>;
+  return (
+    typeof session.accessToken === "string" &&
+    session.accessToken.length > 0 &&
+    session.tokenType === "bearer" &&
+    isSparkUser(session.user)
+  );
+};
+
+const loadStoredSession = (): AuthSession | null => {
+  const raw = localStorage.getItem(AUTH_STORAGE_KEY);
+  if (!raw) return null;
+
+  try {
+    const parsed: unknown = JSON.parse(raw);
+    return isAuthSession(parsed) ? parsed : null;
+  } catch {
+    return null;
+  }
+};
+
+export const authSession = ref<AuthSession | null>(loadStoredSession());
+export const currentUser = computed(() => authSession.value?.user ?? null);
+export const isLoggedIn = computed(() => authSession.value !== null);
+
+setBackendToken(authSession.value?.accessToken ?? null);
+
+export const setAuthSession = (session: AuthSession): void => {
+  authSession.value = session;
+  localStorage.setItem(AUTH_STORAGE_KEY, JSON.stringify(session));
+  setBackendToken(session.accessToken);
+};
+
+export const logout = (): void => {
+  authSession.value = null;
+  localStorage.removeItem(AUTH_STORAGE_KEY);
+  setBackendToken(null);
+};