[FrekiManagarm]

Summary

Adds docs/phase-0-gate.md for LUM-552: the scenarios, measures and numbered pass thresholds that decide whether the network half of Phase 0 is passed. They are written before the first run of the campaign, so the thresholds cannot drift towards the results.

• 6 network profiles, 12 gate scenarios (~2 h) and a 4-scenario smoke run (~20 min);
• 8 blocking thresholds, each with a one-line justification, plus measures that are recorded but do not block;
• an execution protocol and an explicit list of what the gate does not cover.

Origin and revisions

The document was written in the former monorepo on 2026-09-22 (FrekiManagarm/lumyx#13). That PR was closed without merging when the repo was split. It is ported here with the revisions below, each dated in §7 of the document:

• Audio thresholds are now read per stream. A stream is one publisher's audio as received by one subscriber. It is healthy when neither end is degraded.
• Why: the SFU cannot repair audio, because str0m only negotiates NACK for video. Concealment on a degraded stream therefore measures the network and Opus FEC, not the SFU.
• B1 is split:
  • B1a: < 3 % concealment on healthy streams.
  • B1b: the SFU adds no audio loss on any stream.
• B2 and B3 now apply to healthy streams only. The original B3 counted audio from the degraded publisher, which would have failed S5 regardless of the SFU.
• New prerequisite: export the SFU's drop counters (LUM-709). B1b cannot be measured without them.
• Deployment target is OVH Cloud, and document paths are this repo's.

Test plan

• Documentation only, no code change