Implement Connection Timeout for Customer Conversations after Chat Server Restore

As of now, in the case of Chat Server failover, the Chat Server:

1. Restores all conversations (that are not ended yet) from real-time database using Database Connector APIs.
2. Customer socket reconnects and Customer Gadget sends the customer info and conversation info to Chat Server.
3. Chat Server binds the customer socket ID to that conversation and the conversation continues normally.

However, if:

1. The customer closed the chat window and never reconnected.
2. The conversation will remain non-closed in the real-time database and in Chat Server memory.

Proposed Solution:

Chat Server should set a reconnect time after it restores the conversations from the real-time database. In this way, if a customer does not reconnect, the conversation will be closed and will not remain in the real-time database & Chat Server memory for an indefinite time period.