api and storage restructure

lib/api/marianumcloud/nextcloud_ocs.dart

@@ -0,0 +1,33 @@
+import '../../model/account_data.dart';
+import '../../model/endpoint_data.dart';
+
+/// Shared helpers for Nextcloud OCS v2 endpoints.
+///
+/// Three call sites previously duplicated the same header dictionary and the
+/// same URI scaffolding (TalkApi, AutocompleteApi, FileSharingApi). Anything
+/// that talks to `https://<domain>/<base>/ocs/v2.php/...` should go through
+/// these two helpers so additions like a new header or a different auth
+/// scheme only need to change here.
+class NextcloudOcs {
+  NextcloudOcs._();
+
+  /// The standard OCS request header set: JSON accept, OCS API marker,
+  /// HTTP Basic auth from the active [AccountData].
+  static Map<String, String> headers() => {
+        'Accept': 'application/json',
+        'OCS-APIRequest': 'true',
+        'Authorization': AccountData().getBasicAuthHeader(),
+      };
+
+  /// Builds an OCS URI by appending [pathSuffix] under `/ocs/v2.php/` of
+  /// the configured Nextcloud endpoint. Query parameters are converted to
+  /// strings (Uri rejects non-string values).
+  static Uri uri(String pathSuffix, {Map<String, dynamic>? queryParameters}) {
+    final endpoint = EndpointData().nextcloud();
+    return Uri.https(
+      endpoint.domain,
+      '${endpoint.path}/ocs/v2.php/$pathSuffix',
+      queryParameters?.map((key, value) => MapEntry(key, value.toString())),
+    );
+  }
+}