dynamic-launcher: Make desktop file executable

[JakobDev]

The dynamics launcher portal is currently not working under KDE, as KDE requires desktop files to be executable for some reason. This fixes it.

[davidedmundson]

as KDE requires desktop files to be executable for some reason

That's not a completely true story, it shouldn't apply for installed applications, and at most it gives a prompt.

The dynamics launcher portal is currently not working under KDE,

Can you expand on this please.

[JakobDev]

That's not a completely true story, it shouldn't apply for installed applications, and at most it gives a prompt.

There is no prompt. It just shows a Notification. The only way to fix this is by making the desktop file executable., which is not suitable for a normal user.

Can you expand on this please.

The desktop file is installed, but it can't be launched due to missing permission.

[GeorgesStavracas]

Changed to draft so nobody accidentally merges it

[Sodivad]

Hi this prompt/failure was due to not accounting for desktop files linked into the applications directory
Fixed via https://invent.kde.org/frameworks/kconfig/-/commit/6772deba4c2682f1faf8967ba8200db48528f2b2

[GeorgesStavracas]

Given the last comment, I'll close this PR. Thanks for looking at it on the KDE side!