Platform notifications added to CLI and Dashboard

Developers and users now receive platform-wide notifications directly where they work. The web dashboard displays notifications in the sidebar — a new panel shows announcements, changelogs, and platform events that admins can create and manage. The CLI fetches and displays notifications during the trigger dev and trigger login commands, with a --skip-platform-notifications flag to disable the check if desired.

What makes this powerful is the discovery system. Notifications can include file pattern matching rules — a notification only appears when certain files exist (or don't exist) in the project, or when specific content is found in those files. This means alerts can be context-aware: show a notification about a new integration only when the relevant configuration files are present.

The notification system supports multiple surfaces (WEBAPP, CLI), scopes (USER, PROJECT, ORGANIZATION, GLOBAL), and tracking interaction state (seen, clicked, dismissed) per user. The CLI uses Redis to track how many times a user has seen a notification and can limit display frequency. All notification content renders markdown in the dashboard and uses a custom color markup format in the terminal.

This lives across the monorepo: database schema in internal-packages/database, backend services in apps/webapp/app/services, UI components in the webapp's navigation, CLI commands in packages/cli-v3, and supporting utilities for discovery and color rendering.