feat: add preset avatar picker

apps/taro/src/pages/student/student.css

@@ -131,6 +131,115 @@
   background: #f8fbff;
 }
 
+.profile-card {
+  display: flex;
+  align-items: center;
+  gap: 22px;
+  padding: 24px;
+  border: 1px solid #dbe3ee;
+  border-radius: 8px;
+  background: #fff;
+}
+
+.profile-avatar {
+  flex: 0 0 116px;
+  width: 116px;
+  height: 116px;
+  border: 1px solid #bfdbfe;
+  border-radius: 8px;
+  background: linear-gradient(135deg, #dbeafe, #eff6ff);
+  color: #1d4ed8;
+  text-align: center;
+}
+
+.profile-avatar.female {
+  border-color: #fbcfe8;
+  background: linear-gradient(135deg, #fce7f3, #fff1f2);
+  color: #be185d;
+}
+
+.profile-avatar-mark {
+  display: block;
+  font-size: 48px;
+  font-weight: 850;
+  line-height: 116px;
+}
+
+.profile-card-main {
+  flex: 1;
+  min-width: 0;
+}
+
+.avatar-choice-grid {
+  display: grid;
+  grid-template-columns: repeat(2, minmax(0, 1fr));
+  gap: 12px;
+  margin-top: 18px;
+}
+
+.avatar-choice {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+  min-width: 0;
+  min-height: 88px;
+  padding: 14px;
+  border: 1px solid #e2e8f0;
+  border-radius: 8px;
+  background: #f8fafc;
+}
+
+.avatar-choice.active {
+  border-color: #2563eb;
+  background: #eff6ff;
+}
+
+.avatar-choice.busy {
+  opacity: 0.72;
+}
+
+.avatar-choice-icon {
+  flex: 0 0 54px;
+  width: 54px;
+  height: 54px;
+  border-radius: 8px;
+  background: #dbeafe;
+  color: #1d4ed8;
+  text-align: center;
+}
+
+.avatar-choice-icon.female {
+  background: #fce7f3;
+  color: #be185d;
+}
+
+.avatar-choice-mark {
+  display: block;
+  font-size: 28px;
+  font-weight: 850;
+  line-height: 54px;
+}
+
+.avatar-choice-copy {
+  min-width: 0;
+}
+
+.avatar-choice-title {
+  display: block;
+  color: #0f172a;
+  font-size: 24px;
+  font-weight: 780;
+  line-height: 1.25;
+}
+
+.avatar-choice-meta {
+  display: block;
+  margin-top: 4px;
+  color: #64748b;
+  font-size: 20px;
+  line-height: 1.25;
+}
+
 .list-stack {
   display: flex;
   flex-direction: column;