refactor(notification): 删 AnnouncementBanner 废弃文件

AnnouncementBanner 在 v0.12.6 公告改 modal 之后就已经废弃了,
VideoGenerationPage L148 注释明确写"公告已改为弹窗,旧的横幅不再显示",
现在公告整合到 Notification 表后,无任何 import 引用,清理。

同步删 AnnouncementBanner.module.css 配套样式。
typecheck 0 error,smoke 全过。

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

web/src/components/AnnouncementBanner.module.css

@@ -1,81 +0,0 @@
-.banner {
-  display: flex;
-  align-items: center;
-  gap: 10px;
-  padding: 10px 16px;
-  /* 深色 - 紫青渐变玻璃 */
-  background: linear-gradient(90deg, rgba(108, 99, 255, 0.10), rgba(0, 184, 230, 0.08));
-  border-left: 3px solid var(--color-primary);
-  border-bottom: 1px solid var(--color-border-soft);
-  backdrop-filter: var(--bf-glass-md);
-  -webkit-backdrop-filter: var(--bf-glass-md);
-  box-shadow: inset 0 1px 0 var(--color-inset-highlight);
-  font-size: 13px;
-  color: var(--color-text-primary);
-  line-height: 1.5;
-  flex-shrink: 0;
-}
-
-[data-theme="light"] .banner {
-  /* 浅色 - 暖米色 chip */
-  background: var(--color-chip-warm-bg);
-  border-left-color: var(--color-chip-warm-border);
-  border-bottom-color: var(--color-chip-warm-border);
-  color: var(--color-chip-warm-text);
-}
-
-[data-theme="light"] .icon {
-  color: var(--color-chip-warm-badge-text);
-}
-
-.icon {
-  flex-shrink: 0;
-  color: var(--color-primary);
-}
-
-.marqueeWrapper {
-  flex: 1;
-  overflow: hidden;
-  position: relative;
-  mask-image: linear-gradient(90deg, transparent, #000 5%, #000 95%, transparent);
-  -webkit-mask-image: linear-gradient(90deg, transparent, #000 5%, #000 95%, transparent);
-}
-
-.marqueeText {
-  display: inline-block;
-  white-space: nowrap;
-  animation: marquee 20s linear infinite;
-  padding-left: 100%;
-}
-
-.marqueeWrapper:hover .marqueeText {
-  animation-play-state: paused;
-}
-
-@keyframes marquee {
-  0% {
-    transform: translateX(0);
-  }
-  100% {
-    transform: translateX(-100%);
-  }
-}
-
-.closeBtn {
-  flex-shrink: 0;
-  background: none;
-  border: none;
-  color: var(--color-text-secondary);
-  cursor: pointer;
-  padding: 4px;
-  display: flex;
-  align-items: center;
-  justify-content: center;
-  border-radius: 4px;
-  transition: all 0.15s;
-}
-
-.closeBtn:hover {
-  color: var(--color-text-primary);
-  background: var(--color-bg-hover);
-}

web/src/components/AnnouncementBanner.tsx

@@ -1,34 +0,0 @@
-import { useEffect, useState } from 'react';
-import { videoApi } from '../lib/api';
-import styles from './AnnouncementBanner.module.css';
-
-export function AnnouncementBanner() {
-  const [text, setText] = useState('');
-  const [dismissed, setDismissed] = useState(false);
-
-  useEffect(() => {
-    videoApi.getAnnouncement().then(({ data }) => {
-      if (data.enabled && data.announcement) {
-        setText(data.announcement);
-      }
-    }).catch(() => {});
-  }, []);
-
-  if (!text || dismissed) return null;
-
-  return (
-    <div className={styles.banner}>
-      <svg className={styles.icon} width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
-        <path d="M22 17H2a3 3 0 0 0 3-3V9a7 7 0 0 1 14 0v5a3 3 0 0 0 3 3zm-8.27 4a2 2 0 0 1-3.46 0" />
-      </svg>
-      <div className={styles.marqueeWrapper}>
-        <span className={styles.marqueeText}>{text}</span>
-      </div>
-      <button className={styles.closeBtn} onClick={() => setDismissed(true)} title="关闭">
-        <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
-          <path d="M18 6L6 18M6 6l12 12" />
-        </svg>
-      </button>
-    </div>
-  );
-}