core: funds are released with huge delay for failed-to-place trade

[norwnd]

When Client is unable to place a trade due to Server rejecting it, for example:

2025-01-19 14:07:09.195 [ERR] CORE: notify: |ERROR| (order) In-Flight Order Error - In-Flight order with ID 3 failed: new order request with DEX server dex.decred.org:7232 market dcr_btc failed: rpc error: error code 36: failed funding validation

Client funds are locked and only released on the next wallet balance update (BTC wallet in this case) which might happen tens of minutes later (eg. upon next BTC block being mined, or upon Bison wallet restart).

Instead funds should be released immediately.

The following change seems to be resolving this issue: norwnd@b985e49

notes:

• it also should account for funds reserved for Redeems/Refunds
• there is also minor refactoring in there for ErrorCloser to make the intentions around its usage explicit