feat: add Phase 1 V2 clean-cutover snapshot contract

[Pigbibi]

Scope

• Add the frozen clean-cutover schema, offline materializer, strict readback, and synthetic bounded tests.

Validation

• PYTHONPATH=src python3 -m pytest tests/test_soxl_tqqq_clean_cutover_snapshot.py -q
• python3 -m ruff check src/us_equity_snapshot_pipelines/soxl_tqqq_clean_cutover_snapshot.py tests/test_soxl_tqqq_clean_cutover_snapshot.py
• python3 -m compileall -q src/us_equity_snapshot_pipelines/soxl_tqqq_clean_cutover_snapshot.py
• Schema JSON parse and exact three-file scope check.

No providers, credentials, real data, calendar generation, strategy, plugin activation, or live actions.

[github-actions]

🤖 Codex PR Review

✅ Merge allowed: 2 finding(s) reported but none are blocking

ℹ️ Other Findings

1. 🟡 [MEDIUM] Security in src/us_equity_snapshot_pipelines/soxl_tqqq_clean_cutover_snapshot.py

_reserve() only protects the final path component with O_NOFOLLOW. os.lstat(parent) and os.open(parent, ...) still traverse symlinks in ancestor components, so a caller can pass a destination such as trusted/alias/snapshot where alias is a symlink and make the materializer publish outside the caller-bound tree. That defeats the new filesystem-state safety contract and can place snapshots in an unintended directory without tripping validation. (line 290)

Suggestion: Resolve the destination one component at a time with openat(..., O_NOFOLLOW) plus inode checks (or openat2(..., RESOLVE_NO_SYMLINKS|RESOLVE_BENEATH) on Linux) instead of validating only the final component.

2. 🟡 [MEDIUM] Reliability in src/us_equity_snapshot_pipelines/soxl_tqqq_clean_cutover_snapshot.py

_read_member() does a stat(..., follow_symlinks=False) and then a blocking os.open() on the same name. If another process replaces manifest.json, payload.json, or publication.json with a FIFO or device after the stat check, strict_readback_clean_cutover_snapshot() can block indefinitely before the post-open fstat() runs. This makes the new public readback path vulnerable to a local DoS on any mutable snapshot directory. (line 397)

Suggestion: Open publication members with _NONBLOCK, validate os.fstat(fd) on the opened descriptor before reading, and avoid relying on the pre-open stat result for safety-critical checks.

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Review by Codex PR Review bot • PR

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

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[Pigbibi]

Fail-closed: the sole authorized consolidated remediation budget is exhausted and the guarded merge remained BLOCKED after exact-head checks. Closing unmerged and parking per authority.

[chatgpt-codex-connector]

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Reviewed commit: ae01237735

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[chatgpt-codex-connector]

💡 Codex Review

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Reviewed commit: d09aea1560

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[chatgpt-codex-connector]

Reject invalid symbols before JSON serialization

When a caller supplies a row whose symbol is a very large string, _canonical(normalized_row) duplicates and UTF-8-encodes the entire value before the size bound is checked, even though the symbol cannot match either fixed symbol for the pair. A sufficiently large value can therefore cause excessive allocation or MemoryError despite MAX_MEMBER_BYTES; validate membership in PAIR_SYMBOLS[pair_id] or conservatively bound the string before serialization.

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[chatgpt-codex-connector]

Apply identity bounds during strict readback

When a self-consistent publication contains a source_identity or producer_identity longer than MAX_MEMBER_BYTES // 16 but still fits within the one-megabyte manifest limit, strict readback accepts it after the hashes are recomputed, while _build_members rejects the same identity through _require_identity. Use that validator here too so strict readback does not admit evidence the materializer cannot produce.

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[Pigbibi]

Closing unmerged per final remediation authority hard-stop: complete review produced new unresolved findings after the final authorized batch; no further remediation is authorized.