[FEATURE]: Add active AI sessions indicator to project icons in sidebar #14430

Feature hasn't been suggested before.

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Describe the enhancement you want to request

Problem
Users cannot see which projects currently have active AI sessions. They have to switch between projects or check each one individually to know the status.

Proposed solution
Add a visual indicator (spinner) to project icons in the sidebar. The indicator should appear in the top-left corner of the project icon when at least one session in the project or its sandboxes has a "busy" or "retry" status.