Add SourceOS interaction substrate for Noetica and AgentTerm

[mdheller]

Summary

Adds a shared SourceOS interaction substrate so Noetica and AgentTerm become different surfaces over the same governed task/event/governance contract rather than parallel bespoke chat surfaces.

This tranche adds:

• schemas/SourceOSInteractionEvent.json
• examples/sourceos-interaction-event.json
• docs/contract-additions/sourceos-interaction-substrate.md
• tools/validate_sourceos_interaction_examples.py
• dedicated SourceOS Interaction Substrate CI workflow

Contract posture

OpsHistoryEvent remains the local-first operational event ledger. SourceOSInteractionEvent is the noetic/chat/task projection that can be embedded in, referenced by, or derived from OpsHistory.

Noetica owns browser chat, model-selection, steering UX, and inline governance trail. AgentTerm owns terminal-native / Matrix-first operator flow, approvals, event tailing, and trace rendering. Neither surface owns model routing, memory durability, tool grants, policy admission, or execution evidence.

Validation

Local schema check was performed before commit with jsonschema.Draft202012Validator.check_schema and example validation against schemas/SourceOSInteractionEvent.json.

Dedicated CI added:

python tools/validate_sourceos_interaction_examples.py

Downstream follow-up

After merge:

• Noetica should emit this event shape for standalone and SourceOS task completions.
• AgentTerm should ingest/render this event shape as a terminal governance trace.
• Superconscious, AgentPlane, Memory Mesh, Agent Registry, and Policy Fabric should attach refs rather than moving authority into either surface.

Notes

Catalog README update is intentionally deferred to the next small PR if this contract shape is accepted, to avoid mixing discovery/catalog churn with the first substrate contract review.