Add NeqSim risk framework Colab notebooks

[EvenSol]

Summary

Adds a dedicated notebooks/risk/ learning lane for the NeqSim Operational Risk Simulation Framework.

New notebooks

• Operational risk, availability, and production impact
  • builds a NeqSim gas-processing ProcessSystem
  • uses ProductionImpactAnalyzer
  • ranks equipment criticality from process-coupled production loss
  • demonstrates DegradedOperationOptimizer
  • reads reliability data
  • runs OperationalRiskSimulator Monte Carlo availability analysis
  • exposes an agentic pattern from condition -> process state -> consequence -> risk -> degraded operation
• LOPA and SIS risk framework
  • uses the current SISIntegratedRiskModel API
  • adds an initiating event and BPCS IPL
  • builds a SIF with SafetyInstrumentedFunction.builder()
  • performs LOPA and independently checks the arithmetic
  • adds a PFD sensitivity plot
  • clearly separates software demonstration from governed hazard-study assumptions

Also adds notebooks/risk/README.md as the Colab landing page and follow-on roadmap.

The examples are based on the current NeqSim risk documentation and use the supported Python jneqsim gateway.

VALIDATION PENDING CI / COLAB EXECUTION: notebooks are structurally valid JSON and use current documented NeqSim APIs, but a full fresh Colab run has not been executed in this session.