Minimize Forced Refreshes for Stall

[GODrums]

Currently, the extension re-fetches the stall for every new selected item, effectively rendering the local cache useless.

This PR changes this behavior to utilize the cached response until a guaranteed change occurs (e.g. an item is listed through the extension).

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Note

Use cached stall data by default and only force-refresh after listing an item.

• Inventory UI (src/lib/components/inventory/selected_item_info.ts)
  • Add forceRefresh param (default false) to refreshStallData and pass it to gStallFetcher.fetch.
  • On list modal close with listingId, call refreshStallData(true) to force-refresh.
  • Initial/normal stall fetches now use cache by default.

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