feat: Implement SAR Update Sheet for creating and sending SAR markers

lib/widgets/contacts/section_header.dart

@@ -0,0 +1,45 @@
+import 'package:flutter/material.dart';
+
+class SectionHeader extends StatelessWidget {
+  final String title;
+  final int count;
+  final IconData icon;
+
+  const SectionHeader({
+    super.key,
+    required this.title,
+    required this.count,
+    required this.icon,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 8),
+      child: Row(
+        children: [
+          Icon(icon, size: 20),
+          const SizedBox(width: 8),
+          Text(
+            title,
+            style: Theme.of(context).textTheme.titleMedium?.copyWith(
+                  fontWeight: FontWeight.bold,
+                ),
+          ),
+          const SizedBox(width: 8),
+          Container(
+            padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 2),
+            decoration: BoxDecoration(
+              color: Theme.of(context).colorScheme.primaryContainer,
+              borderRadius: BorderRadius.circular(12),
+            ),
+            child: Text(
+              count.toString(),
+              style: Theme.of(context).textTheme.labelSmall,
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}