Move auth and timezone hooks into dedicated hook files

frontend/src/providers/AuthProvider.tsx

@@ -10,7 +10,6 @@
 import {
   createContext,
   useCallback,
-  useContext,
   useMemo,
   useState,
 } from "react";
@@ -25,7 +24,7 @@ interface AuthState {
   expiresAt: string | null;
 }
 
-interface AuthContextValue {
+export interface AuthContextValue {
   /** `true` when a valid session token is held in state. */
   isAuthenticated: boolean;
   /**
@@ -41,7 +40,7 @@ interface AuthContextValue {
 // Context
 // ---------------------------------------------------------------------------
 
-const AuthContext = createContext<AuthContextValue | null>(null);
+export const AuthContext = createContext<AuthContextValue | null>(null);
 
 const SESSION_KEY = "bangui_token";
 const SESSION_EXPIRES_KEY = "bangui_expires_at";
@@ -97,22 +96,3 @@ export function AuthProvider({
 
   return <AuthContext.Provider value={value}>{children}</AuthContext.Provider>;
 }
-
-// ---------------------------------------------------------------------------
-// Hook
-// ---------------------------------------------------------------------------
-
-/**
- * Access authentication state and actions.
- *
- * Must be called inside a component rendered within `<AuthProvider>`.
- *
- * @throws {Error} When called outside of `<AuthProvider>`.
- */
-export function useAuth(): AuthContextValue {
-  const ctx = useContext(AuthContext);
-  if (ctx === null) {
-    throw new Error("useAuth must be used within <AuthProvider>.");
-  }
-  return ctx;
-}