🔧 Tightened RTTcode Schema (experiment IDs, seeds, lineage)

Below is a drop‑in upgrade to the RTTcode v1.0 schema.

It adds:

• experiment_id — globally unique experiment lineage
• seed — deterministic RNG seed for reproducibility
• trial — optional sub‑run index
• tags — arbitrary labels for grouping
• provenance — where this packet came from (engine, version, user, etc.)

All additions are optional but strongly recommended for research, debugging, and reviewer reproducibility.

How it fits into the full schema#

You simply add "experiment" to the top‑level properties and optionally to required if you want strict reproducibility.

"properties": {
  "rtt_version": {...},
  "tick": {...},
  "entities": {...},
  "environment": {...},
  "intent": {...},
  "experiment": { "$ref": "#/$defs/experiment" }
}

This keeps RTTcode clean, extensible, and reviewer‑friendly.