feat(Mobile Schedule): 유튜브 스타일 추천 검색어 리스트 추가

- 드롭다운 대신 컨텐츠 영역 전체에 추천 검색어 표시
- 입력값에 따른 실시간 필터링
- 키패드 검색 버튼(Enter) 클릭 시 키패드 닫기
- 검색 결과 모드에서는 autoFocus 비활성화

frontend/src/pages/mobile/public/Schedule.jsx

@@ -27,6 +27,13 @@ function MobileSchedule() {
     const [calendarViewDate, setCalendarViewDate] = useState(() => new Date(selectedDate));  // 달력 뷰 날짜
     const [calendarShowYearMonth, setCalendarShowYearMonth] = useState(false);  // 달력 년월 선택 모드
     const contentRef = useRef(null);  // 스크롤 초기화용
+    const searchContainerRef = useRef(null); // 검색 컨테이너 (외부 클릭 감지용)
+    const searchInputRef = useRef(null); // 검색 입력 필드 (키패드 닫기용)
+    
+    // 검색 추천 관련 상태
+    const [showSuggestions, setShowSuggestions] = useState(false);
+    const [selectedSuggestionIndex, setSelectedSuggestionIndex] = useState(-1);
+    const [originalSearchQuery, setOriginalSearchQuery] = useState(''); // 필터링용 원본 쿼리
 
     // 검색 모드 진입 함수 (history 상태 추가)
     const enterSearchMode = () => {
@@ -38,7 +45,10 @@ function MobileSchedule() {
     const exitSearchMode = () => {
         setIsSearchMode(false);
         setSearchInput('');
+        setOriginalSearchQuery('');
         setSearchTerm('');
+        setShowSuggestions(false);
+        setSelectedSuggestionIndex(-1);
     };
 
     // 뒤로가기 버튼 처리
@@ -175,6 +185,26 @@ function MobileSchedule() {
         };
     }, [showCalendar]);
 
+    // 검색 추천 드롭다운 외부 클릭 감지
+    useEffect(() => {
+        const handleClickOutside = (event) => {
+            if (searchContainerRef.current && !searchContainerRef.current.contains(event.target)) {
+                setShowSuggestions(false);
+                setSelectedSuggestionIndex(-1);
+            }
+        };
+        
+        if (showSuggestions) {
+            document.addEventListener('mousedown', handleClickOutside);
+            document.addEventListener('touchstart', handleClickOutside);
+        }
+        
+        return () => {
+            document.removeEventListener('mousedown', handleClickOutside);
+            document.removeEventListener('touchstart', handleClickOutside);
+        };
+    }, [showSuggestions]);
+
     // 카테고리 색상
     const getCategoryColor = (categoryId) => {
         const category = categories.find(c => c.id === categoryId);
@@ -257,27 +287,75 @@ function MobileSchedule() {
             {/* 툴바 (헤더 + 날짜 선택기) */}
             <div className="mobile-toolbar-schedule shadow-sm z-50">
                 {isSearchMode ? (
-                    <div className="flex items-center gap-3 px-4 py-3">
+                    <div className="flex items-center gap-3 px-4 py-3 relative" ref={searchContainerRef}>
                         <div className="flex-1 flex items-center gap-2 bg-gray-100 rounded-full px-4 py-2 min-w-0">
                             <Search size={18} className="text-gray-400 flex-shrink-0" />
                             <input
+                                ref={searchInputRef}
                                 type="text"
                                 inputMode="search"
                                 enterKeyHint="search"
                                 placeholder="일정 검색..."
                                 value={searchInput}
-                                onChange={(e) => setSearchInput(e.target.value)}
+                                onChange={(e) => {
+                                    setSearchInput(e.target.value);
+                                    setOriginalSearchQuery(e.target.value);
+                                    setShowSuggestions(true);
+                                    setSelectedSuggestionIndex(-1);
+                                }}
+                                onFocus={() => setShowSuggestions(true)}
                                 onKeyDown={(e) => {
-                                    if (e.key === 'Enter') {
+                                    // 필터링은 원본 쿼리 기준으로 유지
+                                    const dummySuggestions = ['성수기', '성수기 이채영', '이채영 먹방', 'NOW TOMORROW', '하얀 그리움', '콘서트', '월드투어'].filter(s => 
+                                        s.toLowerCase().includes(originalSearchQuery.toLowerCase())
+                                    ).slice(0, 7);
+                                    
+                                    if (e.key === 'ArrowDown') {
                                         e.preventDefault();
+                                        const newIndex = selectedSuggestionIndex < dummySuggestions.length - 1 
+                                            ? selectedSuggestionIndex + 1 
+                                            : 0;
+                                        setSelectedSuggestionIndex(newIndex);
+                                        if (dummySuggestions[newIndex]) {
+                                            setSearchInput(dummySuggestions[newIndex]);
+                                        }
+                                    } else if (e.key === 'ArrowUp') {
+                                        e.preventDefault();
+                                        const newIndex = selectedSuggestionIndex > 0 
+                                            ? selectedSuggestionIndex - 1 
+                                            : dummySuggestions.length - 1;
+                                        setSelectedSuggestionIndex(newIndex);
+                                        if (dummySuggestions[newIndex]) {
+                                            setSearchInput(dummySuggestions[newIndex]);
+                                        }
+                                    } else if (e.key === 'Enter') {
+                                        e.preventDefault();
+                                        if (selectedSuggestionIndex >= 0 && dummySuggestions[selectedSuggestionIndex]) {
+                                            setSearchInput(dummySuggestions[selectedSuggestionIndex]);
+                                            setSearchTerm(dummySuggestions[selectedSuggestionIndex]);
+                                        } else if (searchInput.trim()) {
                                             setSearchTerm(searchInput);
                                         }
+                                        setShowSuggestions(false);
+                                        setSelectedSuggestionIndex(-1);
+                                        // 키패드 닫기
+                                        searchInputRef.current?.blur();
+                                    }
                                 }}
                                 className="flex-1 bg-transparent outline-none text-sm min-w-0 [&::-webkit-search-cancel-button]:hidden"
-                                autoFocus
+                                autoFocus={!searchTerm}
                             />
                             {searchInput && (
-                                <button onClick={() => { setSearchInput(''); setSearchTerm(''); }} className="flex-shrink-0">
+                                <button 
+                                    onClick={() => { 
+                                        setSearchInput(''); 
+                                        setOriginalSearchQuery('');
+                                        setSearchTerm(''); 
+                                        setShowSuggestions(false);
+                                        setSelectedSuggestionIndex(-1);
+                                    }} 
+                                    className="flex-shrink-0"
+                                >
                                     <X size={18} className="text-gray-400" />
                                 </button>
                             )}
@@ -494,13 +572,48 @@ function MobileSchedule() {
 
             {/* 컨텐츠 영역 */}
             <div className="mobile-content" ref={isSearchMode && searchTerm ? scrollContainerRef : contentRef}>
-            <div className="px-4 pt-4 pb-4">
+            <div className={`px-4 pb-4 ${isSearchMode && !searchTerm ? 'pt-0' : 'pt-4'}`}>
                 {isSearchMode ? (
                     // 검색 모드
                     !searchTerm ? (
-                        // 검색어 입력 전 - 빈 상태
+                        // 검색어 입력 전 - 추천 검색어 리스트 표시 (유튜브 스타일)
+                        <div className="space-y-0">
+                            {(() => {
+                                const dummySuggestions = ['성수기', '성수기 이채영', '이채영 먹방', 'NOW TOMORROW', '하얀 그리움', '콘서트', '월드투어'];
+                                
+                                // 입력값이 있으면 필터링
+                                const filtered = originalSearchQuery.length > 0 
+                                    ? dummySuggestions.filter(s => s.toLowerCase().includes(originalSearchQuery.toLowerCase()))
+                                    : dummySuggestions;
+                                
+                                if (filtered.length === 0) {
+                                    return (
                                         <div className="text-center py-8 text-gray-400">
-                            검색어를 입력하세요
+                                            추천 검색어가 없습니다
+                                        </div>
+                                    );
+                                }
+                                
+                                return filtered.map((suggestion, index) => (
+                                    <button
+                                        key={suggestion}
+                                        onClick={() => {
+                                            setSearchInput(suggestion);
+                                            setSearchTerm(suggestion);
+                                            setShowSuggestions(false);
+                                            setSelectedSuggestionIndex(-1);
+                                        }}
+                                        className={`w-full px-0 py-3.5 text-left flex items-center gap-4 border-b border-gray-100 active:bg-gray-50 ${
+                                            index === selectedSuggestionIndex 
+                                                ? 'bg-primary/5' 
+                                                : ''
+                                        }`}
+                                    >
+                                        <Search size={18} className="text-gray-400 shrink-0" />
+                                        <span className="text-[15px] text-gray-700 flex-1">{suggestion}</span>
+                                    </button>
+                                ));
+                            })()}
                         </div>
                     ) : searchLoading ? (
                         <div className="flex justify-center py-8">