Refactor item caching to store ids

[Maxlego08]

Summary

• replace player cache item lists with fastutil IntList identifiers and keep full items in global maps
• index stored items by owner and add helper methods to resolve ids when rendering menus
• add fastutil dependency to support lightweight id-based caching

Testing

• not run (not requested)

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Codex Task

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Remove expired items from storage when filtering

Expired listings are detected in getItemIds but the loop only calls processExpiredItem and never removes the expired entry from storageItemsById. Because the item stays in the LISTED bucket, every subsequent call that touches the cache re-runs the expiration side effects and the entry continues to be counted as listed (e.g., GlobalPlaceholders#listed_items reads getItems(StorageType.LISTED).size()). The previous iterator-based logic removed expired items, so this regression causes repeated expiration processing and inflated listing counts until a manual removal occurs.

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