[High] Solver Simulation Harness and Strategy Backtesting Tool

[james2177]

Description:
Evolve scripts/solver-bot.ts into a simulation harness that replays historical intent streams against pluggable solver strategies, producing PnL, fill-rate, and slash-risk reports.

Problem Statement & Context:
Prospective solvers can't evaluate economics before bonding capital, and protocol parameter changes (fill windows, fees, auction curves) can't be evaluated against realistic behaviour.

Scope & Acceptance Criteria:

• Replay engine reading archived intents/prices; deterministic simulated clock.
• Strategy interface (onIntent, onQuoteRequest, onTick) with two reference strategies.
• Parameter sweep mode for protocol params (fill window, fee bps) producing comparative reports.
• Out of scope: live trading.

Implementation Guidelines:

1. Key Files/Modules: scripts/solver-bot.ts, new tools/simulator/, reuse src/auctions/, src/fees/, src/routing/.
2. Design/Architecture: Import pure domain modules directly (no Nest bootstrap) — reinforces keeping domain logic pure.
3. Edge Cases/Constraints: Must replay 1M intents in < 5 minutes.
4. Testing: Determinism test (same seed ⇒ identical report).

Definition of "Done": Common DoD; docs in scripts/README.md.

Resources:

• Design reference: N/A (backend-only)
• scripts/solver-bot.ts

---

Common Definition of "Done" (applies in addition to the criteria above):

• Code written, tested, and documented (TSDoc on public APIs, README/runbook/ADR updates where behaviour changes).
• All acceptance criteria met; npm run lint, npm run typecheck, npm test, npm run test:e2e pass in CI.
• PR follows .github/PULL_REQUEST_TEMPLATE, uses a Conventional Commit title (enforced by commitlint), includes test output / metrics screenshots, and references the issue.
• New env vars are added to .env.example variants and src/config/env.validation.ts (the check:env-drift script must pass).
• Reviewed and approved by at least one CODEOWNER.

[ayandipe]

@ayandipe has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hello Maintainer,

Kindly assign issue to me for prompt and precise resolution.

Kind Regards

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[olaide2001]

@olaide2001 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi Maintainer, I would love to work on this issue because I have relevant experience. Pls assign it to me

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[benedictworks-home]

@benedictworks-home has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi maintainer, please assign

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[drips-wave]

Congratulations, @benedictworks-home! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on September 30, 2026.

🧑‍💻 @benedictworks-home: 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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