fix(mux): reject invalid TS adaptation-only lengths

[kixelated]

Problem

The TS importer accepted adaptation-only packets shorter than the required 183-byte adaptation field and payload packets whose adaptation field consumed the payload. Malformed media and dedicated-PCR packets consequently escaped the damaged-unit path.

Approach

Validate adaptation length against the packet's adaptation-field-control before parsing optional fields. Adaptation-only packets require 183 bytes; adaptation-plus-payload allows at most 182. Valid zero-length adaptation-plus-payload packets remain accepted.

Validation: the two new regressions fail on the previous implementation and pass with this fix. Nix just rs test -p moq-mux passed (1205 tests, one skipped), just check, just test interop --all, and quest check passed.

Impact

No public API or wire-format change. Malformed source TS input is counted as damage on the existing recovery path; valid input keeps its clock and media behavior. Removed the completed quest and its README entry.

Alternatives

Rejecting only optional-field overruns misses legal AFC-specific bounds. Keeping short adaptation-only packets accepts malformed input. Recommendation: apply the packet-control rule at the existing validator. No unresolved API decision.

Follow-ups

Backport to release after this main fix lands. No release branch or version was changed. Other in-flight TS importer drafts, including PMT split #5220, may need a small textual rebase; no semantic dependency.

(Written by GPT-6)

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📥 Commits

Reviewing files that changed from the base of the PR and between c840926 and ad0c02c.

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📒 Files selected for processing (3)

• quest/m1/README.md
• quest/m1/ts-adaptation-only.md
• rs/moq-mux/src/container/ts/import.rs

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[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-10T22:40:51.368136Z	ad0c02c	Draft marked ready

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[kixelated]

Merge validation: CI passes for ad0c02c, Codex completed its review with no findings, and no review threads remain. The user approved merging this fix through the queue.

This rejects invalid TS adaptation-field lengths through the existing damaged-input recovery path, with regression coverage. There are no public API or wire-format changes. A release backport remains a separate follow-up.

(Written by GPT-6)