feat(analytics): model context window utilization warning

[SurviveM]

Requirements

Track token consumption ratio per session per model. Sessions exceeding 80% utilization should be marked red. Sessions exceeding 95% should trigger a warning. Predict out-of-context risk before it happens.

Verification

1. Open session list page → check the context % column
2. Trigger a large file operation to push a session toward the limit
3. Verify red flag appears at 80%+ and warning appears at 95%+
4. Verify the warning is dismissible and the session remains usable

[ymkiux]

This feature request has been reviewed and prioritized.

Assessment:

• High value for user experience - prevents context window exhaustion surprises
• Implementation complexity: Medium - requires session token tracking and UI indicators
• Dependencies: Session management infrastructure (already in place)

Proposed approach:

• Track token consumption per session
• Add visual indicators (80% = red, 95% = warning)
• Implement dismissible warning system

Will be considered for next sprint planning.

[ymkiux]

Implemented in PR #166. Features added:

• Token utilization percentage calculation per session
• Visual indicators with color coding (green/orange/red)
• Pulse animation for warning (80%+) and critical (95%+) states
• Percentage badge displayed in session list header