Refactor Web-UI Events, Tasks and Notifications

[mhmdk0]

• Replace WebUI dictionaries with typed classes: Events, Notification, and Task.
• Use an event stream (SSE) for sending/receiving events.
• Add max log-event caps in both frontend and backend to limit stored logs and what’s shown in the panel, fixing memory spikes under heavy output.
• Introduce a new Chunk event that batches multiple log events with size and age limits to improve throughput and avoid flooding.

[github-actions]

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[mhmdk0]

Commit 6a210d6

• Fixed events streaming issue.
• Updated medperf-login to use the new events streaming logic and applied some front-end improvements.
• Fixed some front-end bugs in benchmark workflow test page.
• Fixed the issue preventing dataset owners from seeing the Export Dataset button.
• Corrected container compatibility test page redirection.
• Added counter badges for benchmark owners to view dataset and model associations, as well as results.