Feat: add Demo-Factory connection fixtures

[smithaldon1]

Summary

• Adds checked-in Demo-Factory OPC-UA, MQTT, and BACnet read-only connection profile fixtures plus a combined connection_profiles.json store.
• Updates Compose/runtime environment documentation so FIP can load the fixture store and use verified Demo-Factory host endpoints.
• Refreshes the architecture doc with the updated MVP and long-term architecture diagrams.
• Adds contract coverage that validates the fixtures against ProtocolConnectionProfile, constrains configured source references, and checks the no-secret/no-production-data safety boundary.

Closes #237

Test Evidence

• make test-contract passed: 91 passed.
• .venv/bin/python -m pytest packages/factory-events/tests/test_demo_factory_connection_profile_fixtures.py services/simulator/tests/test_connector_safety_model_docs.py services/simulator/tests/test_docker_compose_runtime_docs.py passed: 22 passed.
• docker compose -f infra/docker/docker-compose.yml config passed.
• make test-integration passed: 99 passed, 2 skipped.
• make lint passed.
• make typecheck passed.
• make test passed: 275 passed, 4 skipped.
• cd apps/web && npm test passed: 18 passed.

Docs Impact

• Updated runtime Compose docs, troubleshooting, connector safety docs, data contract docs, learning log, .env.example, and architecture diagrams.

Follow-Up Work

• Feature: Add connector worker runtime #238 should implement the connector worker runtime that loads these profiles and produces normalized FactoryEvents.
• Source-to-FactoryEvent mappings remain explicit unmapped/default references until mapping work expands them.

[smithaldon1]

Reviewed and approved for merge