Add a chart empty state

[arisu6804]

Summary

Add a chart empty state.

Context

Tracking issue for the YieldVault frontend. Open to contributors.

Acceptance criteria

• Implement the change described above
• Add or update automated tests
• Update the relevant documentation

[grantfox-oss]

🦊 GrantFox — @AugistineCreates has been assigned to this issue as part of the Official Campaign | FWC26 campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #213)
2. Your PR will be reviewed by the YieldVault-Org maintainers

Good luck! Track your progress on GrantFox.