[G01] Prove Scale Set delivery, acquisition and drain contracts

[jjangg96]

Goal

Select and pin a supported Scale Set integration path with demonstrated recovery at message acknowledgement, acquisition and JIT boundaries.

Create one active Codex goal from the statement above when this issue is dispatched. The Project Goal field is a work specification; it does not start an agent. Do not invent a token budget.

Execution contract

Field	Value
Goal key	G01
Stage	M0 - Evidence gates
Initial status	Ready
Primary agent	gpt-5.6-luna / max
Priority / risk	P0 / High
Test profiles	offline, trusted-live-github

Use one issue branch/worktree and one focused PR. Independent Luna max review is required for authentication, protocol, concurrency, resource ownership, cleanup or service identity boundaries; other changes need independent contract review. Model fields are routing instructions, not GitHub user assignments.

Dependencies

None. This issue is initially Ready.

Dependencies must be Done before implementation begins. A new issue is not blocked simply because its future evidence has not been collected.

Scope

Isolated protocol spike and ADR; compare release v0.4.0 with audited commit cb0405b2d874500e75ae34eff8d582ab75956b45. Do not implement production providers or copy the demo shutdown policy.

TDD and failure evidence

1. Red: fake session server reproduces ACK-before-callback crash and missing lifecycle callback.
2. Cover pre/post ACK, acquisition, >50 events, repeated/stale statistics, 202, 401/403/429, callback failure and session replacement with deterministic barriers.
3. Test idle-assignment races while drain withdraws capacity; mocks alone cannot prove server deregistration/acquisition behavior. Run an explicitly authorized disposable private live canary before closing the gate.

Capture a meaningful failing case before the implementation, then green evidence and relevant refactor checks. Tooling/prose-only work uses appropriate negative checks without artificial application tests. Live/runtime profiles require reviewed commits, a dedicated trusted test environment and explicit authorization for the concrete experiment. Public PR CI uses hosted environments without credentials. Planned or skipped tests never count as passed.

Acceptance criteria

• Record exact module/runner versions and supported JIT bootstrap transports, including any secret exposure.
• Choose high-level listener plus independent reconciliation OR a lower-level supported message loop; do not simply reverse ordering without evidence.
• Document recoverable state versus quarantine for lost callback/request IDs; no exactly-once claim.
• Publish sanitized live contract evidence or keep the gate unresolved; obtain independent Luna max protocol review.
• Record exact validation commands, actual results, skipped/live-test gaps and applicable rollback notes in the PR.
• Independent review is resolved and the focused PR is merged under the repository execution policy.
• Update issue/Project accurately; mark the active goal complete only after all required evidence and work are complete.

Safety invariants

Preserve existing manual runners; no global Docker prune/context switching, broad process kill, implicit App enrollment, busy-job cancellation during ordinary scale-down or transparent workflow replay. Use only verifiably owned resources. Keep management credentials and raw secret-bearing SDK errors out of worker environments, logs, fixtures and commits; per-worker JIT transport follows G01. Native pools remain trusted-only.

Design references

• Architecture and gates
• Language decision
• Security design
• TDD strategy
• Goal/model execution policy
• Ordered backlog

[jjangg96]

Offline SDK contract evidence merged in #22 (1396e20) after independent Astra xhigh review. Actual SDK v0.4.0 and the audited comparison commit passed the fault-contract race tests and static checks. The record separates recoverable aggregate demand from quarantined acquisition/JIT uncertainty.

This issue remains in progress: authorized private live evidence is still required. A separately opt-in canary driver is now being prepared for independent review before any live resource creation. No existing manual runners or credentials were changed, and dependent production integration stays gated.