Remove database runtime implementations from core

[vaibhav-i]

Summary

• remove built-in SQL/Mongo verification and database reset implementations from ax-eval core
• require explicit arena-owned providers for database verification and cleanup, and remove mongodb, mysql2, pg, and @types/pg from the root package
• delegate both legacy DAEB runtime aliases through the explicit arena compatibility map to the trusted-workflow fail-closed boundary
• retain generic HTTP/Asana reset compatibility while unsupported reset/reclaim fails at the provider boundary before resolving obsolete credentials, templates, or scope
• harden import/package guards and preserve v1 SQL/Mongo declarations as provider inputs only

Verification

• Node 22.23.1
• npm test: 576 core tests and 208 arena tests
• npm run typecheck
• npm run build
• npm run pack:check (34 core files, 86 arena files)
• core and arena npm --cache .npm-cache pack --dry-run
• git diff --check

All tests are offline and keyless. No live or credentialed evaluation was run.

Independent audit

The independent reviewer found one P2 contract bug: unsupported database reset eagerly resolved core credentials before reporting the missing provider. Client/scope resolution is now lazy, and auth-required ${MISSING_*} regressions cover both direct reset and exec-plan --reclaim.

The final exact-commit audit of 446df3bd2bf73d27f430f4c32051853a4e7fcf28 was clean.

Stack

Base: #198 trusted workflow cell fan-out.

Rollback: revert this PR to restore the built-in core database runtime while leaving the explicit arena providers intact.

Next slice: remove the remaining DAEB execution loops and policy from core.

[github-actions]

Normalized records diff

Overall is a macro-average of participating surface scores. Agents are never averaged together.

Overall by agent

Product	Agent	Base pass@1	Head pass@1	Δ	Base pass³	Head pass³	Surfaces
fixture-db	claude-code	92.9%	92.9%	+0.0 pp	78.6% (11/14)	78.6% (11/14)	2
fixture-db	codex	78.6%	78.6%	+0.0 pp	64.3% (9/14)	64.3% (9/14)	2

Surface cells

Product	Agent	Surface	Base pass@1	Head pass@1	Δ	Base pass³	Head pass³	Latency ms	Cost USD	Tokens	Harness version
fixture-db	claude-code	api	85.7%	85.7%	+0.0 pp	71.4% (5/7)	71.4% (5/7)	1100 → 1100	0.4200 → 0.4200	3350 → 3350	2.1.5 → 2.1.5
fixture-db	claude-code	cli	100.0%	100.0%	+0.0 pp	85.7% (6/7)	85.7% (6/7)	1300 → 1300	0.5100 → 0.5100	3720 → 3720	2.1.5 → 2.1.5
fixture-db	codex	api	85.7%	85.7%	+0.0 pp	71.4% (5/7)	71.4% (5/7)	1200 → 1200	— → —	3600 → 3600	0.121.0 → 0.121.0
fixture-db	codex	cli	71.4%	71.4%	+0.0 pp	57.1% (4/7)	57.1% (4/7)	1500 → 1500	— → —	4100 → 4100	0.121.0 → 0.121.0

Operational metrics are context only and never affect ranking.