Update PROJECT_STRUCTURE.md to reflect Overview/Assets/Wallets/Soroban/Rankings/Explorer IA

[christabel888]

Context: PROJECT_STRUCTURE.md currently documents the repo layout -- likely still describes the old flat nav/explorer framing rather than the new grouped IA from #175.

Where:

• PROJECT_STRUCTURE.md (repo root)

What to do:

• Update the structure doc to reflect the Overview/Assets/Wallets/Soroban/Rankings/Explorer grouping once Restructure sidebar.tsx nav groups: Overview, Assets, Wallets, Soroban, Rankings, Validators, Explorer #175 lands, so new contributors aren't reading stale IA docs.
• Also update the root README.md to lead with the new one-sentence pitch: "Stellar Insights is an open-source analytics platform that turns Stellar blockchain data into actionable ecosystem intelligence through dashboards, rankings, wallet analytics, and Soroban metrics."

Definition of done:

• PROJECT_STRUCTURE.md matches the actual nav structure after Restructure sidebar.tsx nav groups: Overview, Assets, Wallets, Soroban, Rankings, Validators, Explorer #175-Update bottom-nav.tsx to mirror new information architecture #180 ship
• Root README opens with the new one-sentence pitch, no remaining "explorer" framing in top-level docs

[JohnOluB]

I'll update the PROJECT_STRUCTURE.md file to accurately reflect the current information architecture, including the Overview, Assets, Wallets, Soroban, Rankings, and Explorer sections.

My approach will be to:

Review the current project structure and compare it with the existing application.
Identify any missing or outdated sections in the documentation.
Update PROJECT_STRUCTURE.md to match the latest IA while keeping the document clear, consistent, and easy to navigate.
Verify that the structure accurately represents the current codebase before submitting a PR.

[grantfox-oss]

🦊 GrantFox — @JohnOluB 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 #191)
2. Your PR will be reviewed by the Stellar-Insightss maintainers

Good luck! Track your progress on GrantFox.