fix(ui): /companies Hero 居中对齐并显示完整简介

- hero-inner align-items 改 center, logo 与文字垂直居中
- 去掉 hero-desc 4 行截断与 max-height, 公司简介完整显示
- logo 图片去掉 padding, 纯 contain 居中

Co-Authored-By: Claude <noreply@anthropic.com>

offer_frontend/src/views/portal/CompanyListView.vue

@@ -171,7 +171,7 @@ onMounted(async () => {
   padding: 0 24px;
   display: flex;
   gap: 36px;
-  align-items: flex-start;
+  align-items: center;
 }
 .hero-logo {
   flex-shrink: 0;
@@ -182,7 +182,7 @@ onMounted(async () => {
   border: 1px solid var(--border);
   background: var(--bg-page);
 }
-.hero-logo img { width: 100%; height: 100%; object-fit: contain; padding: 8px; }
+.hero-logo img { width: 100%; height: 100%; object-fit: contain; }
 .logo-placeholder {
   width: 100%;
   height: 100%;
@@ -226,11 +226,6 @@ onMounted(async () => {
   font-size: 13px;
   line-height: 1.9;
   color: var(--text-muted);
-  max-height: 120px;
-  overflow: hidden;
-  display: -webkit-box;
-  -webkit-line-clamp: 4;
-  -webkit-box-orient: vertical;
   margin-bottom: 20px;
 }
 .hero-btn {