feat: Implement push notification suppression for active chats, prevent duplicate self-messages, update the chat typing indicator, and add back buttons to static screens.

lib/features/contact/presentation/screens/contact_screen.dart

@@ -31,7 +31,36 @@ class _ContactScreenState extends State<ContactScreen> {
     return ListView(
       padding: EdgeInsets.zero,
       children: [
-        const SizedBox(height: 18),
+        // Back button
+        Padding(
+          padding: const EdgeInsets.fromLTRB(16, 8, 16, 0),
+          child: Align(
+            alignment: Alignment.centerLeft,
+            child: GestureDetector(
+              onTap: () {
+                if (Navigator.of(context).canPop()) {
+                  Navigator.of(context).pop();
+                } else {
+                  context.go('/home');
+                }
+              },
+              child: Container(
+                width: 36,
+                height: 36,
+                decoration: BoxDecoration(
+                  color: AppColors.primaryDark.withValues(alpha: 0.08),
+                  shape: BoxShape.circle,
+                ),
+                child: const Icon(
+                  Icons.arrow_back_ios_new_rounded,
+                  color: AppColors.primaryDark,
+                  size: 18,
+                ),
+              ),
+            ),
+          ),
+        ),
+        const SizedBox(height: 10),
         _buildTitle(),
         const SizedBox(height: 10),
         _buildDescription(),