feat: podpora dark mode

client/src/components/Header.tsx

@@ -2,7 +2,7 @@ import { useEffect, useState } from "react";
 import { Navbar, Nav, NavDropdown } from "react-bootstrap";
 import { useAuth } from "../context/auth";
 import SettingsModal from "./modals/SettingsModal";
-import { useSettings } from "../context/settings";
+import { useSettings, ThemePreference } from "../context/settings";
 import FeaturesVotingModal from "./modals/FeaturesVotingModal";
 import PizzaCalculatorModal from "./modals/PizzaCalculatorModal";
 import RefreshMenuModal from "./modals/RefreshMenuModal";
@@ -54,7 +54,7 @@ export default function Header() {
         return n !== Infinity && String(n) === str && n >= 0;
     }
 
-    const saveSettings = (bankAccountNumber?: string, bankAccountHolderName?: string, hideSoupsOption?: boolean) => {
+    const saveSettings = (bankAccountNumber?: string, bankAccountHolderName?: string, hideSoupsOption?: boolean, themePreference?: ThemePreference) => {
         if (bankAccountNumber) {
             try {
                 // Validace kódu banky
@@ -99,6 +99,9 @@ export default function Header() {
         settings?.setBankAccountNumber(bankAccountNumber);
         settings?.setBankAccountHolderName(bankAccountHolderName);
         settings?.setHideSoupsOption(hideSoupsOption);
+        if (themePreference) {
+            settings?.setThemePreference(themePreference);
+        }
         closeSettingsModal();
     }