[Bug]: Generated "Desktop Entry" file uses wrong quotation and is considered "invalid" upon validation

[ChillyVanilly77]

Describe the bug

When performing the "programs list" entry context-menu action (currently) named "Add Desktop Entry",
the generated content of that Desktop Entry file uses single-quotes (') instead of double-quotes (") for arguments containing space(s) that aren't meant to separate args, but rather something like a name or so.

Generated Desktop Entry file for the fan-made "Pokemon Infinity":

[Desktop Entry]
Name=Pokemon Infinity
Exec=flatpak run --command=bottles-cli com.usebottles.bottles run -p 'Pokemon Infinity' -b 'Gaming' -- %u
Type=Application
Terminal=false
Categories=Application;
Icon=<some-base-path>/games/bottles/Gaming/icons/Pokemon Infinity.png
Comment=Launch Pokemon Infinity using Bottles.
StartupWMClass=Pokemon Infinity
Actions=Configure;
[Desktop Action Configure]
Name=Configure in Bottles
Exec=flatpak run com.usebottles.bottles -b 'Gaming'

When trying to "install" that Desktop Entry file using the utility desktop-file-install (which 1st performs a validation of the content) – since the sandboxed/flatpak app(s)-specific *.desktop-files aren't looked-up/included when searching for apps using some kind of "Applications"-look-up button or shortcut (like a "Start" menu button in KDE Plasma, or "Applications" in COSMIC etc.) – , it errors out with 6x "error"s, 1 for each present non-escaped single-quote.
Output:

/usr/share/applications/Gaming--Pokemon Infinity--1764608204.090144.desktop: error: value "flatpak run --command=bottles-cli com.usebottles.bottles run -p 'Pokemon Infinity' -b 'Gaming' -- %u" for key "Exec" in group "Desktop Entry" contains a reserved character ''' outside of a quote
/usr/share/applications/Gaming--Pokemon Infinity--1764608204.090144.desktop: error: value "flatpak run --command=bottles-cli com.usebottles.bottles run -p 'Pokemon Infinity' -b 'Gaming' -- %u" for key "Exec" in group "Desktop Entry" contains a reserved character ''' outside of a quote
/usr/share/applications/Gaming--Pokemon Infinity--1764608204.090144.desktop: error: value "flatpak run --command=bottles-cli com.usebottles.bottles run -p 'Pokemon Infinity' -b 'Gaming' -- %u" for key "Exec" in group "Desktop Entry" contains a reserved character ''' outside of a quote
/usr/share/applications/Gaming--Pokemon Infinity--1764608204.090144.desktop: error: value "flatpak run --command=bottles-cli com.usebottles.bottles run -p 'Pokemon Infinity' -b 'Gaming' -- %u" for key "Exec" in group "Desktop Entry" contains a reserved character ''' outside of a quote
/usr/share/applications/Gaming--Pokemon Infinity--1764608204.090144.desktop: error: value "flatpak run com.usebottles.bottles -b 'Gaming'" for key "Exec" in group "Desktop Action Configure" contains a reserved character ''' outside of a quote
/usr/share/applications/Gaming--Pokemon Infinity--1764608204.090144.desktop: error: value "flatpak run com.usebottles.bottles -b 'Gaming'" for key "Exec" in group "Desktop Action Configure" contains a reserved character ''' outside of a quote
Error on file "/home/<username>/.var/app/com.usebottles.bottles/data/applications/Gaming--Pokemon Infinity--1764608204.090144.desktop": Failed to validate the created desktop file

According to the The Exec key section at the official freedesktop(dot)org website,
the single-quote is one of the "reserved" characters, and should therefore ideally just use the non-reserved one, i.e. double-quotation, or escaping the reserved chars instead.

To Reproduce

1. Enter into some existing bottle
2. Click the 3-dots button of a specific existing program from the list of programs to trigger its context menu
3. select the action "Add Desktop Entry"
4. Attempt to install (for it to show up in a "Start"-like menu or wherever one would look-up available apps) or just validate the produces Desktop Entry file located (probably) under the path ~/.var/app/com.usebottles.bottles/data/applications/<bottle-name>--<program-name>--<digits>.<digits>.desktop
5. Observe produced error(s)

Package

Flatpak from Flathub

Distribution

CachyOS

Debugging Information

Official Package: true
Version: '60.1'
DE/WM: plasma
Display:
    X.org: true
    X.org (port): :0
    Wayland: true
Graphics:
    vendors:
        amd:
            vendor: amd
            envs:
                DRI_PRIME: '1'
            icd: /usr/share/vulkan/icd.d/radeon_icd.x86_64.json:/usr/lib/x86_64-linux-gnu/GL/vulkan/icd.d/radeon_icd.x86_64.json:/usr/lib/i386-linux-gnu/GL/vulkan/icd.d/radeon_icd.i686.json
    prime:
        integrated: null
        discrete: null
Kernel:
    Type: Linux
    Version: 6.17.9-2-cachyos
Disk:
    Total: 16695152640
    Free: 16694980608
RAM:
    MemTotal: 31.1GiB
    MemAvailable: 26.7GiB
Bottles_envs: null

Troubleshooting Logs

Additional context

NOTE: this may of course be considered an "overkill" bug report, but the primary intention is to have it properly logged as a ticket and provide addition help/infos for those users perhaps wondering about what that did exactly. If there are not current or future plans to handle those file "better" regarding "ease-of-use" for users, and should just be something rather documented for users on "How to …" do this for themselves, I would be happy to write a docs entry for this if desired, let me know.

[ChillyVanilly77]

I've submitted a PR for it => #4248