[Bug] Chat conversation history is lost on page refresh - No session persistence

[SandeepChauhan00]

🐛 Bug Description

Chat conversation history is completely cleared when the page is refreshed (F5/Ctrl+R). Users lose their entire conversation including queries and responses, forcing them to start from scratch.

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🔄 Steps to Reproduce

1. Open the Knowledge Space Agent chat interface (http://localhost:3000)
2. Send a message: "find EEG brain datasets"
3. Wait for the response (success or error)
4. Press F5 or Ctrl+R to refresh the page
5. Observe the chat interface

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✅ Expected Behavior

• Conversation history should persist after page refresh
• Previous queries and responses should remain visible
• User should be able to continue the conversation seamlessly

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❌ Actual Behavior

• All conversation history is cleared
• Only the default welcome message appears:

  "Hello! I'm your INCF KnowledgeSpace assistant..."

• User loses all previous queries and responses

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📸 Evidence

Before Refresh:
You: find EEG brain datasets
KnowledgeSpace Assistant: [Response displayed]

After Refresh:
KnowledgeSpace Assistant: Hello! I'm your INCF KnowledgeSpace assistant...
[Previous conversation GONE]

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💥 Impact

Impact Area	Description
User Experience	Users lose their research progress
Productivity	Must re-type queries after accidental refresh
Data Loss	No way to recover previous conversations

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🛠️ Suggested Solution

LocalStorage Persistence

// Save conversation to localStorage
localStorage.setItem('chatHistory', JSON.stringify(messages));

// Restore on page load
const savedHistory = localStorage.getItem('chatHistory');
if (savedHistory) {
  setMessages(JSON.parse(savedHistory));
}

🌍 Environment

• Browser: Chrome
• OS: Windows
• App Version: Latest

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📋 Acceptance Criteria

• Conversation persists after page refresh (F5)
• Conversation persists after browser tab close/reopen
• Works across all major browsers