add basic account creation

Foxchat.Identity/Database/Models/Token.cs

@@ -24,4 +24,17 @@ public class Token : BaseModel
 
         return (token, hash);
     }
+
+    public static (string, Token) Create(Account? account, Application application, string[] scopes, Instant expires)
+    {
+        var (token, hash) = Generate();
+        return (token, new()
+        {
+            Hash = hash,
+            Scopes = scopes,
+            Expires = expires,
+            Account = account,
+            Application = application,
+        });
+    }
 }