[Docs] Replace Web UI preview with animated demo

[realrazdev]

Summary

Replace the static web-preview.png image in the README with an animated demo showcasing the Web UI.

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Context

Context

The README currently uses a static screenshot (web-preview.png) to showcase the Web UI.

Replace it with a short animated demo (GIF preferred) to better demonstrate the interactive experience, including the AI Explain feature.

For setup and usage of the Explain feature, refer to USAGE.md. This issue only covers the README demo and should not duplicate existing documentation.

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Requirements

• Ensure Ollama is installed, running, and configured before recording the demo (see USAGE.md for setup instructions).
• Replace the current web-preview.png in the README with an animated demo.
• Record a short GIF (5–15 seconds preferred).
• Demonstrate:
  • Opening the Web UI
  • Creating or selecting a task
  • Using the Explain feature
  • Switching between Summary, Deep Analysis, and Action Plan
• Keep the demo concise and high quality.

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Non-goals

• Do not modify application code.
• Do not update CLI documentation.
• Do not duplicate information already documented in USAGE.md.

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Acceptance Criteria

• The static web-preview.png is replaced with an animated demo.
• The demo showcases the Explain feature.
• The README renders correctly on GitHub.
• No application code changes are required.

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What's next?

Thanks for contributing! We'd love to see another PR from you.

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