Add graph limit modal and SNS notification infrastructure

[jfrench9]

Summary

This PR introduces a graph provisioning limit flow that gates users when creating new graphs, along with supporting backend infrastructure for SNS email notifications and secret management. The feature adds a modal-based UI to inform users when they've reached their graph limit and provides a form to request limit increases.

Changes

Infrastructure & CI/CD

• SNS Notification Email: Added SNS_NOTIFICATION_EMAIL parameter propagation through deploy-app.yml, prod.yml, and staging.yml workflows to support email-based alerting
• RoboSystems Secret ARN: Added ROBOSYSTEMS_SECRET_ARN handling in the deployment workflow for secure secret management
• CloudFormation Template: Extended cloudformation/template.yaml with ~79 lines of new resource definitions, likely including SNS topic/subscription resources and related IAM permissions for notification delivery

Frontend — Graph Limit Flow

• GraphLimitModal.tsx (new): A modal component that surfaces when users hit their graph creation limit, providing clear feedback and a pathway to request increases
• GraphLimitForm.tsx (new, 277 lines): A comprehensive form component for users to submit graph limit increase requests, likely including validation, form fields for justification, and submission handling
• graphs/new/content.tsx (modified): Integrated the new limit check logic into the graph creation flow, conditionally rendering the limit modal/form instead of or alongside the existing creation UI (~115 lines modified, net +91)

Key UI/UX Improvements

• Users are now clearly informed when they've reached their graph provisioning limit rather than encountering an opaque error
• A structured form allows users to request limit increases directly within the app flow
• Modal pattern keeps users in context without navigating away from the graph creation page

Breaking Changes

• Environment Configuration Required: Deployments now require SNS_NOTIFICATION_EMAIL to be set in the workflow environment/secrets for prod and staging. Missing configuration may cause deployment failures.
• CloudFormation Stack Update: The template changes will trigger a stack update — ensure proper change set review before deploying to production.

Testing Notes for Reviewers

• Verify the graph limit modal appears when a user has reached their max graph count
• Test the limit increase form submission — confirm validation, error states, and successful submission behavior
• Test the happy path where users are under the limit and can create graphs normally (no regression)
• Confirm SNS email subscription is created and confirmation email is sent upon stack deployment
• Verify the ROBOSYSTEMS_SECRET_ARN is correctly resolved and accessible in the deployed environment
• Test modal dismiss/close behavior and ensure users can navigate back cleanly
• Check form accessibility: keyboard navigation, focus management within the modal, screen reader announcements

Browser Compatibility Considerations

• Modal component should be tested across Chrome, Firefox, Safari, and Edge for proper overlay rendering and scroll locking behavior
• Form validation UX (inline errors, focus management) should be verified on mobile browsers (iOS Safari, Chrome Android)
• Ensure the modal backdrop and z-index layering doesn't conflict with existing UI elements like navigation or toast notifications

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🤖 Generated with Claude Code

Branch Info:

• Source: feature/improved-graph-provisioning-flow
• Target: main
• Type: feature

Co-Authored-By: Claude noreply@anthropic.com