continue first full balancing round

docs/progression_design.md

@@ -373,15 +373,9 @@ in `requirements.md` and the git history). Still open:
    one matching deposit tile). Touches REQ-BLD-MINER ("every asteroid
    tile is equivalent" no longer holds), REQ-GW-ASTEROID-EXPAND /
    REQ-EXP-*, `world.toml`, and `visuals.toml`.
-6. **Investigate team-1 bias in balancing arenas.** In arena round 1
-   (July 2026), team 1 won all three mirror matches with large margins
-   (8/20, 3/6, 1/2 survivors). Re-run mirrors repeatedly; if team 1
-   wins consistently, find and fix the asymmetry (spawn geometry, tick
-   processing order, target-selection tie-breaking). Mirror matches
-   must be statistically symmetric or every arena result carries a
-   side-dependent error.
-7. **Log remaining HP in the balancing arena results.** Win/loss alone
-   hides the margin ("1/1 battleship" can mean 95% or 5% HP left). Add
-   the surviving entities' remaining HP fraction (or a per-team total
-   EHP percentage) to the arena end state, so equal-threat matchups can
-   be tuned toward near-draws quantitatively.
+6. **Verify the balancing arena end condition.** Arena round 1's
+   station-assault log showed the arena "(running)" with every ship on
+   both sides destroyed — per REQ-BAL-SIM-END the station-less team
+   should have lost the moment its last ship died. Round 2 ended
+   correctly, so it may only be a log-snapshot artifact; confirm, and
+   fix the end condition if it can genuinely idle in that state.