Unload far-away areas past a budget and regenerate them in place

[valuecodes]

What

• Part 5/5 of Post-MVP additions: unload areas the player has left behind, so a large repository no longer grows the JS heap (~1.4 MB per built area) and GPU geometry/textures without bound.
• AreaStore.evict drops a built area but keeps its reserved place; ensure regenerates it deterministically at the same offset, so rooms, portals and return points are unchanged. AreaWorld.unloaded lists them; zones, checkAreas and the maps treat them as built (outlines with data-area-state="unloaded", counted in n/total).
• createUnloader (area-budget.ts) keeps at most 12 areas loaded, least recently visited first. Pins are bounded: entry, the player's area, navigation's unit, the top frame's ends and the portal ahead. Backspace and return portals generate the top caller's area first.
• Pre-generation on sight stays for pending areas only; an unloaded area regenerates when stepped into, so looking along a wall of portals does not churn.

How to test

pnpm typecheck
pnpm lint
pnpm knip
pnpm test
pnpm build
pnpm --filter web dev # open http://localhost:3000/?code=self&stats=1, walk through more than 12 module portals: areas holds near 12, geo/tex level off, walking back regenerates an area in the same place (Tab map)

Security review

No security-impacting changes.

🤖 Generated with Claude Code

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[chatgpt-codex-connector]

Codex Review Summary

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Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-14T13:09:57.993195Z	35a5908	PR opened

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