trade_ui: address small bugs

[andrei8l]

Summary

SUMMARY: None

Purpose of change

Address small bugs with the new trade_ui and remove old workarounds inherited from trading_window

Fixes #43239: contained liquids have negative prices
Fixes #52816: invlet and keybinding conflicts
Fixes #52817: allied NPCs still check balance before accepting
Fixes #46873: npc_trading::trade() can cause a segfault if window refresh is triggered while traded items are manipulated
Can't trade for, or even expand some containers (ex: zipper bag): remove TRADER_AVOID from all container items

Describe the solution

Please see individual commits. These are all small fixes.

Describe alternatives you've considered

N/A

Testing

Additional context

[Night-Pryanik]

Any chance this PR will fix #14619?

[andrei8l]

Any chance this PR will fix #14619?

If I'm reading this chain right, that dialogue option first generates a random debt with parameters defined in json here

Cataclysm-DDA/data/json/npcs/TALK_COMMON_OTHER.json

Line 381 in 564d632

"effect": [ { "add_debt": [ [ "TRUST", 1 ], [ "VALUE", 3 ], [ "ALTRUISM", 2 ], [ "TOTAL", 300 ] ] }, "give_equipment" ],

then picks an item that can fit in the NPC's total debt, then subtracts the item's value from the debt here

Cataclysm-DDA/src/npctalk_funcs.cpp

Line 577 in 564d632

p.op_of_u.owed -= giving[chosen].price;

At the moment I don't see any way to properly remove the fake debt added in the first step, sorry. It probably requires changes to JSON processing so you'd have a single-step effect like "effect": [ { "give_equipment": [ ...paremeters here... ] } ] instead of the two steps used now.

[wapcaplet]

Nice work! I retested the associated bugs in your branch, and can confirm:

• Liquids (and their containers, and their containers' containers, etc.) have correct positive prices.
• Allied NPCs accept trades that put them in debt (or gifts) without complaint.
• When trading an item inside a wielded backpack for an item that I must wield, I get prompted to drop the backpack, the trade goes through ok, and there is no crash.
• I already changed my keybinding and can't easily test the new default, but TAB works to swap panes as expected.

[andrei8l]

@wapcaplet thanks a lot for testing and tracking down these bugs!