Indexer: document entity ownership and derived fields

[Otaiki1]

Build location

Work primarily in indexer/src/database/entities. Keep related tests/docs beside that package unless this issue explicitly calls for a cross-package update.

Why this matters

Entities include raw chain state and derived query state; contributors need to know which fields are source-of-truth.

What to build

• Add entity-level comments or docs for Raffle, Ticket, User, RaffleEvent, PlatformStat, Cursor, DLQ.
• Mark derived fields and their updater handlers.
• Document which fields are safe to recalculate.

Acceptance criteria

• Docs are linked from indexer README.
• New migrations reference ownership rules.

Suggested verification

cd indexer && npm run lint && npm run test && npm run build

[sweetesty]

@sweetesty has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

hi please can i be assigned to this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @sweetesty to this issue.

[charityzarmai]

@charityzarmai has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi maintainer I'm a fullstack developer and can handle this issue please assign it to me thank you.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @charityzarmai to this issue.

[drips-wave]

Congratulations, @charityzarmai! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @charityzarmai: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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