Add Architecture Decision Records (ADRs) for key design choices

[Emeka000]

Summary

The repository implements many non-obvious design choices but the rationale behind them is not documented. New contributors and auditors must reverse-engineer intent from code.

ADRs to Write

1. ADR-001: Why Soroban/Stellar vs other blockchain platforms
2. ADR-002: Storage TTL retention class design (Critical/Operational/Ephemeral)
3. ADR-003: Hash-based privacy for sensitive fields
4. ADR-004: Multi-sig governance threshold design
5. ADR-005: Actor verification caching strategy in shared module
6. ADR-006: Why no-std with WASM target

Format

Each ADR: Context → Decision → Consequences

Acceptance Criteria

• ADR directory created at docs/adr/
• All 6 ADRs written
• README links to the ADR directory

[Emelie-Dev]

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

Hi, I would love to work on this issue.

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

[MaimunaY]

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

Hello Healthy-Stellar, I’m interested in working on this issue #406. I’m confident in my ability to deliver an efficient solution in line with the project guidelines. I’d appreciate the opportunity to contribute to the project. Thank you.

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

[ubermensh-323]

@ubermensh-323 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

hi team kindly assign me i can work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @ubermensh-323 to this issue.

[drips-wave]

Congratulations, @ubermensh-323! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @ubermensh-323: 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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