Build Lumina dashboard shell

[ZuLu0890]

Summary

• Replace the generated Next.js starter page with a Lumina vesting operations dashboard shell.
• Add sections for vault tracking, stream metrics, governance proposals, and compliance health.
• Update page metadata and clean up README encoding, clone URL, and setup guidance.

Why

The repository described a Lumina Network dashboard, but the app still rendered the default Create Next App experience. This change gives the project a product-specific first screen aligned with the documented vesting, governance, and compliance scope.

Validation

• Ran git diff --cached --check successfully before commit.
• Could not run npm run lint or npm run build locally because this environment does not have node/npm on PATH.

Notes

Draft PR so CI/reviewer feedback can be handled before marking ready.
closes #19