feat(chat): 채팅방 상단 캔 배지 및 더보기 전체화면 다이얼로그 추가

- 헤더 우측에 캔 배지(tv_can_badge)와 더보기(iv_more) 추가
- 캔 배지 스타일 적용(배경 #263238, 텍스트 white, v5/h8 패딩, can 아이콘)
- 더보기 클릭 시 전체화면 다이얼로그 표시(플레이스홀더 UI)

app/src/main/res/layout/activity_chat_room.xml

@@ -34,10 +34,10 @@
         android:id="@+id/header_container"
         android:layout_width="0dp"
         android:layout_height="60dp"
-        android:paddingTop="4dp"
         android:background="@android:color/transparent"
         android:paddingHorizontal="16dp"
         android:paddingVertical="8dp"
+        android:paddingTop="4dp"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent"
         app:layout_constraintTop_toTopOf="parent">
@@ -69,7 +69,7 @@
             android:layout_marginStart="12dp"
             android:orientation="vertical"
             app:layout_constraintBottom_toBottomOf="@+id/iv_profile"
-            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintEnd_toStartOf="@+id/ll_can_badge"
             app:layout_constraintStart_toEndOf="@id/iv_profile"
             app:layout_constraintTop_toTopOf="@id/iv_profile">
 
@@ -98,11 +98,55 @@
                 android:textColor="#FFFFFFFF"
                 android:textSize="10sp"
                 app:layout_constraintBottom_toBottomOf="@id/iv_profile"
-                app:layout_constraintEnd_toEndOf="parent"
                 tools:ignore="SmallSp"
                 tools:text="Clone" />
         </LinearLayout>
 
+        <!-- 캔 배지 -->
+        <LinearLayout
+            android:id="@+id/ll_can_badge"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginEnd="10dp"
+            android:background="@drawable/bg_can_badge"
+            android:gravity="center"
+            android:orientation="horizontal"
+            android:paddingHorizontal="10dp"
+            android:paddingVertical="5dp"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toStartOf="@+id/iv_more"
+            app:layout_constraintTop_toTopOf="parent">
+
+            <ImageView
+                android:layout_width="20dp"
+                android:layout_height="20dp"
+                android:layout_marginEnd="4dp"
+                android:contentDescription="@null"
+                android:src="@drawable/ic_can" />
+
+            <TextView
+                android:id="@+id/tv_can_badge"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:fontFamily="@font/pretendard_regular"
+                android:gravity="center"
+                android:textColor="#FFFFFFFF"
+                android:textSize="16sp"
+                tools:text="123,456" />
+
+        </LinearLayout>
+
+        <!-- 더보기 버튼 -->
+        <ImageView
+            android:id="@+id/iv_more"
+            android:layout_width="24dp"
+            android:layout_height="24dp"
+            android:contentDescription="@null"
+            android:src="@drawable/ic_seemore_vertical_white"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintTop_toTopOf="parent" />
+
     </androidx.constraintlayout.widget.ConstraintLayout>
 
     <!-- 안내 메시지 영역 -->