## Context
Adds a feature preview banner toast for the explorer - flagged behind
the configcat flag
<img width="315" height="342" alt="image"
src="https://github.com/user-attachments/assets/9dbd7ffd-02c6-4083-9ca0-266b862e1b5d"
/>
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
- **New Features**
- Added an Explorer preview banner to project layouts when the feature
is enabled.
- Added an “Enable Explorer” call-to-action that opens the feature
preview.
- Banner dismissal is remembered and persists across sessions.
- Added telemetry tracking for banner dismissal and CTA interactions.
- **Bug Fixes**
- Improved banner behavior and stability when displaying database
connection notifications.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Joshen Lim
961fc749d4