feat: update HTML structure and add logo for Weather App; remove unused SVG from WeatherCard

frontend/src/components/Header.tsx

@@ -2,6 +2,7 @@ import React from "react";
 import ChangeAPI from "./ChangeAPI";
 import { useState } from "react";
 import Cookies from "js-cookie";
+import logo from "../assets/cloud-sun-fill.svg";
 
 const Header: React.FC = () => {
   const [apiCard, setApiCard] = useState(false);
@@ -12,7 +13,7 @@ const Header: React.FC = () => {
       <header className="bg-gradient-to-r from-blue-700 via-blue-600 to-blue-500 text-white shadow-lg py-8 px-6 flex items-center justify-between rounded-b-3xl">
         <div className="flex items-center gap-4">
           <img
-            src="/favicon.ico"
+            src={logo}
             alt="Weather App Logo"
             className="w-10 h-10 drop-shadow-lg"
           />

frontend/src/components/WeatherData.tsx

@@ -16,15 +16,6 @@ const WeatherData: React.FC = () => {
     <div className="flex justify-center items-center min-h-[60vh]">
       <div className="bg-white/90 p-10 rounded-2xl shadow-2xl min-w-[320px] text-center border-2 border-blue-200">
         <h2 className="text-3xl font-bold mb-2 text-blue-700 flex items-center justify-center gap-2">
-          <svg
-            className="w-7 h-7 text-blue-400"
-            fill="none"
-            stroke="currentColor"
-            strokeWidth="2"
-            viewBox="0 0 24 24"
-          >
-            <path d="M3 12a9 9 0 0118 0A9 9 0 013 12z" />
-          </svg>
           {weatherData?.name}
         </h2>
         <p className="text-5xl font-extrabold mb-2 text-blue-900">

frontend/src/components/WeatherForm.tsx

@@ -48,16 +48,7 @@ const WeatherCard: React.FC = () => {
   return (
     <div className="w-full max-w-lg mx-auto bg-white/80 rounded-2xl shadow-xl p-8 mt-8">
       <h2 className="text-3xl font-bold mb-4 text-blue-700 flex items-center gap-2">
-        <svg
-          className="w-8 h-8 text-blue-400"
-          fill="none"
-          stroke="currentColor"
-          strokeWidth="2"
-          viewBox="0 0 24 24"
-        >
-          <path d="M3 12a9 9 0 0118 0A9 9 0 013 12z" />
-        </svg>
-        Weather Card
+        Weather
       </h2>
       <p className="mb-2 text-gray-600">
         Current weather will be displayed here.