Project three plausible future scenarios

Use only the evidence in this notebook to project three future scenarios over the next 24 months.

For each of Optimistic, Base Case, and Pessimistic, produce:
1. Headline outcome in one sentence.
2. The 3 key drivers (each with the source that supports it) that would push the world toward this scenario.
3. The strongest piece of counter-evidence in the notebook that argues against this scenario.
4. Three leading indicators — concrete, observable signals over the next 6 months that would tell you this scenario is unfolding.
5. The first decision someone reading this should make differently if they believed this scenario.

End with:
- A probability you'd assign each scenario, summing to 100%, with a one-sentence justification grounded in the sources.
- The single signal that, if observed, would most strongly shift weight between scenarios.

Do not invent drivers or indicators the notebook can't support. Speculation is fine; fabrication is not.