feat: establish simulation scaling baseline

docs/PROJECT_CONTEXT.md

@@ -943,10 +943,21 @@ the need closes. The result and HUD add no quest acceptance, waypoint, tracker,
 save field, RNG draw, or simulation mutation. This completes the Milestone 7
 simulation-garden exit proof.
 
-The next slice should start Milestone 8 with a deterministic headless scaling
-baseline over increasing NPC and event counts. Measure tick throughput,
-serialized-state growth, and retained history before selecting a target
-population or implementing spatial partitions and active/abstract LOD.
+The first Milestone 8 measurement slice is complete. A reusable schema-valid
+headless fixture and CLI runner now measure full-fidelity simulation throughput,
+phase timing, serialized-state growth, retained knowledge, objective event
+growth, and deterministic checksums across 6, 60, and 600 NPCs plus 600 and
+6,000 seeded histories. The reviewed Apple M1 Max baseline reaches 65.84 ticks
+per second for 600 data-only NPCs, above the initial local 50-ticks-per-second
+reference target, while exposing superlinear population cost and rapid
+objective-log growth. Workload details and raw samples live in
+[`docs/benchmarks/`](benchmarks/SIMULATION_SCALING_BASELINE_01.md).
+
+The next slice should build one stable per-tick population view for the
+existing trusted-starving-subject query, which currently rebuilds an all-NPC
+map for each applicable scarce-food decision. Preserve exact selection and
+continuation checksums, rerun the same benchmark, and use the remaining measured
+cost before committing to spatial partitions or active/abstract LOD.
 
 The remaining simulation-garden target still aims for: