GUI: Filtering games list effectively clears selected game even if the selected game matches filter

[antoniou79]

Tested on ScummVM 2026.3.0 on Windows 10 x64 and a recent daily build of 2026.3.1git.

This is a couple of bugs with slightly different bugged behavior, but probably common cause:

BUG 1: Setting a game filter, while having a game selected

1. In ScummVM launcher, in List view, select a game, eg. The Longest Journey
2. Then type a filter that matches the game's title "long"

RESULT: The game selected is "effectively" cleared, meaning that it will still show as selected in the list, but the buttons like Start, Load, Game Options will be disabled until the user clicks on the game's title again. Also oddly, the "Remove Game" is enabled, and clicking it prompts the user to confirm game configuration deletion as expected, but then clicking "YES" results in ScummVM crashing.

BUG 2: Clearing the game filter, while having a game selected.
When clearing the filter, the selected game also gets bugged:

1. Launch ScummVM, type in a filter (eg. "longest")
2. Click a matching title to selected from the list view (for this example "The Longest Journey")
3. The buttons Start, Load, Game Options are enabled and working at this point.
4. Clear the filter by pressing the "X" button.

RESULT: The game still shows as selected *and* the buttons Start,Load,Game Options show as enabled, but pressing them does nothing. Note: Remove Game seems to reponsive though, but I have not tested its results (it prompts to delete game configurations, but I have not tested clicking on Yes).