feat(chat):Added chat history storage to the Q chat for agentic chat

[ashishrp-aws]

Problem

Q chat does not store chat messages in chat history to store the context and have followup conversations with users. For Q Agentic chat we need to unblock this issue.

Solution

• Added chatHistoryStorage which maintains the chat storage.
• We fix maintain history size
• Clear history in case of errors, tab close and session close situations.

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[github-actions]

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