WIP - Replaced get_it + injectable with Provider

lib/core/security/security_context_subject.dart

@@ -0,0 +1,26 @@
+import 'dart:async';
+import 'dart:io';
+
+import 'package:dio/dio.dart';
+import 'package:http/io_client.dart';
+import 'package:http_interceptor/http_interceptor.dart';
+import 'package:paperless_mobile/features/login/model/client_certificate.dart';
+import 'package:rxdart/rxdart.dart';
+
+extension SecurityContextAwareBaseClientSubjectExtension
+    on BehaviorSubject<BaseClient> {
+  ///
+  /// Registers new security context in a new [HttpClient].
+  ///
+
+  BaseClient _createSecurityContextAwareHttpClient(
+    SecurityContext context, {
+    List<InterceptorContract> interceptors = const [],
+  }) {
+    Dio(BaseOptions());
+    return InterceptedClient.build(
+      client: IOClient(HttpClient(context: context)),
+      interceptors: interceptors,
+    );
+  }
+}