[sia] add bucket support

Author: redsolver

lib/store/create.dart

@@ -104,6 +104,7 @@ Map<String, ObjectStore> createStoresFromConfig(
           : siaConfig['busApiUrl'],
       apiPassword: siaConfig['apiPassword']!,
       downloadUrls: [siaConfig['downloadUrl']!],
+      bucket: siaConfig['bucket'] ?? 'default',
       httpClient: httpClient,
     );
   }

lib/store/sia.dart

@@ -14,6 +14,7 @@ class SiaObjectStore extends ObjectStore {
   final String busApiUrl;
   final String workerApiUrl;
   final String apiPassword;
+  final String bucket;
   final Client httpClient;
 
   final List<String> downloadUrls;
@@ -24,7 +25,9 @@ class SiaObjectStore extends ObjectStore {
   final availableBaoOutboardHashes = <Multihash>{};
 
   Uri _getApiUri(String path) {
-    return Uri.parse('$workerApiUrl$path');
+    return Uri.parse('$workerApiUrl$path').replace(queryParameters: {
+      'bucket': bucket,
+    });
   }
 
   @override
@@ -62,6 +65,7 @@ class SiaObjectStore extends ObjectStore {
     required this.apiPassword,
     required this.httpClient,
     required this.downloadUrls,
+    required this.bucket,
   }) {
     _headers = {
       'Authorization': 'Basic ${base64Url.encode(utf8.encode(':$apiPassword'))}'