feat: add refresh control, fallback cache, and last updated indicator to Market Intelligence

[SAYALI8106]

Summary

This PR enhances the Market Intelligence (Tech News) section by implementing the requested improvements from Issue #129.

Changes Made

• Added a manual refresh button using the existing RefreshCw icon.
• Added a fallback mechanism that displays cached news when the API request fails.
• Added a "Last Updated" indicator to show when news was last successfully fetched.
• Added support for force-refreshing news while bypassing cache validation.
• Improved the error state message to guide users toward refreshing.

Closes #129

Type of Change

• Bug fix
• New feature
• Documentation update
• Refactor (no behavior change)
• Chore / tooling
• UI polish

Screenshots / Screen Recording

How to Test

1. Run the project locally.
2. Open the dashboard.
3. Navigate to the Market Intelligence section.
4. Verify that a refresh button appears in the header.
5. Click the refresh button and confirm fresh news is fetched.
6. Verify that the "Updated" timestamp changes after a successful fetch.
7. Simulate an API failure by disabling the network.
8. Confirm cached news is displayed instead of an empty state.
9. Clear local storage and simulate API failure again.
10. Confirm the error message is displayed correctly.

Checklist

• I linked the related issue, if one exists.
• I assigned myself before opening the PR, if required.
• npm run lint passes.
• npm run typecheck passes.
• npm run build succeeds.
• I reviewed my own changes before requesting review.
• I did not change unrelated files.
• I updated documentation if needed.

[SAYALI8106]

@AshutoshDash1999 Please review the PR.