Chore: Scope URLs with account_id (#601)

* Chore: Enable Users to create multiple accounts

Addresses: #402
- migrations to split roles and other attributes from users table
- make changes in code to accommodate this change

Co-authored-by: Pranav Raj Sreepuram <pranavrajs@gmail.com>

app/views/api/v1/accounts/conversations/messages/create.json.jbuilder

@@ -0,0 +1,8 @@
+json.id @message.id
+json.content @message.content
+json.inbox_id @message.inbox_id
+json.conversation_id @message.conversation_id
+json.message_type @message.message_type_before_type_cast
+json.created_at @message.created_at.to_i
+json.private @message.private
+json.attachment @message.attachment.push_event_data if @message.attachment