Player Stock Improvements

What have you done in this MR?

• Player Stock is now cleared from the general store at an interval defined by world.playerstock_clear_mins (defaults to 180 minutes)
• Player Stock can now be recirculated back onto the GE as bot offers when cleared if world.playerstock_bot_offers is true (defaults to true)

This MR attempts to tackle the issue of player stock on the live server constantly being full. It also provides an optional benefit of bolstering bot stock with the items that otherwise would have been completely deleted from the game.

This bonus is not exploitable because in every possible scenario, the offered bot price on the GE will be higher than the price it was sold to the shop for, even at high alch shops.

@ryannathans Test Server - Please set playerstock_clear_mins to something reasonable like 1-5 to make testing this easier for testers

Testers:

• Sell an item to player stock
• Eventually the item should disappear from player stock, and reappear on the GE as bot stock.

Are there any tricky things testers should keep an eye out for?

• No

• Yes, as follows:

• I have tested these changes thoroughly.

• This requires extra testing due to changes to architecture or other similarly risky changes.

• I used the Thanos Tool for any JSON edits where possible, and have attached screenshots of any changes.

• I acknowledge that this contribution will be released under the AGPL license.

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