At every fork in the test graphs, and in the conflict cache tests, the
Rust resolution over an in-memory store must agree with the Python one.
A new test does the same over 40 random graphs of power level,
membership, join rule and topic events, many of which fail auth.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ULdieJyQoHNzeHq42H2M1p