Adding Notification for Capacity Shutdown for 1.1

[jatinkulkarni]

Issue

Description of Changes

Implements FTP Capacity Block Expiration Notification feature for SageMaker extension. Adds three-tier notification system (30min, 10min, 2min warnings) to alert users before capacity block expiration, preventing unexpected data loss.

Key additions:

• capacityBlockWarning.ts - notification display logic
• constant.ts - CB notification constants and metadata interfaces
• extension.ts - monitoring initialization, scheduling, cleanup
• sagemaker.series - patch file registration

Technical highlights:

• Handles setTimeout limits for long-duration blocks (>24 days) via 7-day periodic rechecks
• Auto-reschedules if capacity block extended (1min tolerance)
• Accounts for EC2's 30min shutdown window
• Toast notifications at 30/10min, modal at 2min with "Save All" option

Testing

Tested via GitHub Actions workflow on feature branch with DISABLE_MANGLE=true. Build artifacts generated successfully. Verified notification scheduling logic and timeout handling.

Screenshots/Videos

Additional Notes

Changes limited to SageMaker-specific directories (patches/sagemaker/), enabling SageMaker team self-approval per CODEOWNERS. Feature enhances UX by preventing data loss during capacity block expiration with defensive error handling and graceful degradation.

Backporting

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[aws-ajangg]

Otherwise, LGTM

[jatinkulkarni]

Otherwise, LGTM

Removed those commented out notification messages

[aakashmandavilli96]

LGTM