Backlog: merge related tasks into four and rewrite them

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/agent-log.md

@@ -4,6 +4,13 @@ What agents have done, newest first. Add an entry for every piece of work: the d
 note or request it was for, what changed, the files touched, the tests run, and anything left
 open or not verified. Keep each entry short; the git history has the details.
 
+## 2026-10-24: Backlog combined and rewritten (Claude Code)
+
+- On the owner's request: t12 (exotic ores) and t31 (choosing claims) merged into t13, now
+  "Distinct worlds: generation options, planet presets, exotic ores and a choice of claims";
+  t24 (water fixes) merged into t21, now "Code health: refactor, speed up and test the physics".
+  t2 and t14 rewritten with subtasks. t12, t24 and t31 archived (`tasks/archive/`), not deleted.
+
 ## 2026-10-24: t32: minimap and full map (Claude Code, Codex)
 
 - `src/ui/map.js`: colour cache (`resetMap`, `mapArea`, `updateMap` from the frame loop),