Contracts docs: Database schema reference

[codebestia]

Write apps/backend/docs/contracts-database-schema.md documenting every table in db/schema.ts — users, wallets, conversations, conversationMembers, files, messages, messageEnvelopes, devices, devicePrekeys, tokenTransfers, treasuryProposals, proposalVotes, pushSubscriptions — with every column, type, default, index, and foreign-key relation.

Acceptance criteria:

• Every table has every column documented (name, type, nullability, default, constraint)
• Every index (including partial/unique) and every check constraint is documented with what it enforces and why
• Relations between tables (FKs, cascade behavior) are documented, ideally with a mermaid ER diagram
• Generated directly from the current schema file, then spot-checked against a real pnpm db:generate output

[SHEROSE0]

@SHEROSE0 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi dear maintainer, I'm ready to work on this has I've read through the description please kindly assign it to me and I'll deliver it promptly. Thank you

ℹ️ Repo Maintainers: To accept this application, review their application or assign @SHEROSE0 to this issue.

[Godswillopeyemihub]

@Godswillopeyemihub has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi maintainer can you please assign this issue to me.

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

[drips-wave]

Congratulations, @Godswillopeyemihub! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

🧑‍💻 @Godswillopeyemihub: 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.

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