refactor: remove login/auth for public dashboard

- Remove login page, redirect / to /dashboard directly
- Remove AuthProvider, DashboardGuard from dashboard layout
- Remove use-auth hook and auth API module
- Remove X-Admin-Password header from API client
- Remove logout button from sidebar

services/frontend/src/lib/api/auth.ts

@@ -1,13 +0,0 @@
-import { ApiError, api } from "./client";
-
-export async function login(password: string): Promise<boolean> {
-  try {
-    const resp = await api.post<{ ok: boolean }>("/api/auth/login", {
-      password,
-    });
-    return resp.ok;
-  } catch (err) {
-    if (err instanceof ApiError) return false;
-    throw err;
-  }
-}

services/frontend/src/lib/api/client.ts

@@ -12,27 +12,17 @@ function getBaseUrl(): string {
   if (typeof window === "undefined") return "";
   const protocol = window.location.protocol.replace(":", "");
   const host = window.location.host;
-  // In dev, Next.js proxy can be configured, but default to same-host assumption
   return `${protocol}://${host}`;
 }
 
-function getAuthHeader(): string | null {
-  if (typeof window === "undefined") return null;
-  return localStorage.getItem("admin-password");
-}
-
 export async function apiRequest<T>(
   method: string,
   path: string,
   body?: unknown,
 ): Promise<T> {
   const url = `${getBaseUrl()}${path}`;
-  const password = getAuthHeader();
 
   const headers: Record<string, string> = {};
-  if (password) {
-    headers["X-Admin-Password"] = password;
-  }
   if (body !== undefined) {
     headers["Content-Type"] = "application/json";
   }

services/frontend/src/lib/api/index.ts

@@ -1,4 +1,3 @@
-export { login } from "./auth";
 export { ApiError, api, apiRequest } from "./client";
 export { configApi } from "./config";
 export { dashboardApi } from "./dashboard";

services/frontend/src/lib/hooks/use-auth.tsx

@@ -1,78 +0,0 @@
-"use client";
-
-import {
-  createContext,
-  type ReactNode,
-  useCallback,
-  useContext,
-  useEffect,
-  useState,
-} from "react";
-import { login } from "@/lib/api";
-
-interface AuthContextValue {
-  authenticated: boolean;
-  loading: boolean;
-  login: (password: string) => Promise<boolean>;
-  logout: () => void;
-}
-
-const AuthContext = createContext<AuthContextValue | null>(null);
-
-export function AuthProvider({ children }: { children: ReactNode }) {
-  const [authenticated, setAuthenticated] = useState(false);
-  const [loading, setLoading] = useState(true);
-
-  useEffect(() => {
-    const password = localStorage.getItem("admin-password");
-    if (password) {
-      // Verify stored password still works
-      login(password)
-        .then((ok) => {
-          setAuthenticated(ok);
-          setLoading(false);
-        })
-        .catch(() => {
-          localStorage.removeItem("admin-password");
-          setLoading(false);
-        });
-    } else {
-      setLoading(false);
-    }
-  }, []);
-
-  const handleLogin = useCallback(async (password: string) => {
-    const ok = await login(password);
-    if (ok) {
-      localStorage.setItem("admin-password", password);
-      setAuthenticated(true);
-    }
-    return ok;
-  }, []);
-
-  const handleLogout = useCallback(() => {
-    localStorage.removeItem("admin-password");
-    setAuthenticated(false);
-  }, []);
-
-  return (
-    <AuthContext.Provider
-      value={{
-        authenticated,
-        loading,
-        login: handleLogin,
-        logout: handleLogout,
-      }}
-    >
-      {children}
-    </AuthContext.Provider>
-  );
-}
-
-export function useAuth(): AuthContextValue {
-  const ctx = useContext(AuthContext);
-  if (!ctx) {
-    throw new Error("useAuth must be used within an AuthProvider");
-  }
-  return ctx;
-}