inbox: add GET public inbox key & POST inbox items endpoint (#51)

* inbox: add GET public inbox key && POST inbox items endpoint

* inbox: update SyncItem to support inbox items

* inbox: update post inbox items request payload

* inbox: update post inbox item endpoint

Notesnook.API/Models/Algorithms.cs

@@ -22,5 +22,6 @@ namespace Notesnook.API.Models
     public class Algorithms
     {
         public static string Default => "xcha-argon2i13-7";
+        public static string XSAL_X25519_7 => "xsal-x25519-7";
     }
 }

Notesnook.API/Models/InboxSyncItem.cs

@@ -0,0 +1,70 @@
+/*
+This file is part of the Notesnook Sync Server project (https://notesnook.com/)
+
+Copyright (C) 2023 Streetwriters (Private) Limited
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the Affero GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+Affero GNU General Public License for more details.
+
+You should have received a copy of the Affero GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+using System.ComponentModel.DataAnnotations;
+using System.Runtime.Serialization;
+using System.Text.Json.Serialization;
+
+namespace Notesnook.API.Models
+{
+
+    [MessagePack.MessagePackObject]
+    public class InboxSyncItem : SyncItem
+    {
+        [DataMember(Name = "key")]
+        [JsonPropertyName("key")]
+        [MessagePack.Key("key")]
+        [Required]
+        public EncryptedKey Key
+        {
+            get; set;
+        }
+    }
+
+    [MessagePack.MessagePackObject]
+    public class EncryptedKey
+    {
+        [DataMember(Name = "alg")]
+        [JsonPropertyName("alg")]
+        [MessagePack.Key("alg")]
+        [Required]
+        public string Algorithm
+        {
+            get; set;
+        }
+
+        [DataMember(Name = "cipher")]
+        [JsonPropertyName("cipher")]
+        [MessagePack.Key("cipher")]
+        [Required]
+        public string Cipher
+        {
+            get; set;
+        }
+
+        [JsonPropertyName("length")]
+        [DataMember(Name = "length")]
+        [MessagePack.Key("length")]
+        [Required]
+        public long Length
+        {
+            get; set;
+        }
+    }
+}

Notesnook.API/Models/SyncItem.cs

@@ -111,7 +111,7 @@ namespace Notesnook.API.Models
         public string Algorithm
         {
             get; set;
-        } = Algorithms.Default;
+        }
     }
 
     public class SyncItemBsonSerializer : SerializerBase<SyncItem>