feat: Add scroll-to-event

lib/utils/matrix_identifier_string_extension.dart

@@ -0,0 +1,24 @@
+extension MatrixIdentifierStringExtension on String {
+  /// Separates room identifiers with an event id and possibly a query parameter into its components.
+  MatrixIdentifierStringExtensionResults parseIdentifierIntoParts() {
+    final match = RegExp(r'^([#!][^:]*:[^\/?]*)(?:\/(\$[^?]*))?(?:\?(.*))?$')
+        .firstMatch(this);
+    if (match == null) {
+      return null;
+    }
+    return MatrixIdentifierStringExtensionResults(
+      roomIdOrAlias: match.group(1),
+      eventId: match.group(2),
+      queryString: match.group(3),
+    );
+  }
+}
+
+class MatrixIdentifierStringExtensionResults {
+  final String roomIdOrAlias;
+  final String eventId;
+  final String queryString;
+
+  MatrixIdentifierStringExtensionResults(
+      {this.roomIdOrAlias, this.eventId, this.queryString});
+}