Fix desktop launch, app icons and keyboard parameter editing

.github/release-notes.md

@@ -21,6 +21,19 @@ SolidCraft project Pages URLs; old-name Pages addresses are not permanent aliase
 - **Web:** `solvecraft-web-{version}.zip` is a static site to host yourself.
 - `SHA256SUMS.txt`: `sha256sum -c SHA256SUMS.txt --ignore-missing`.
 
+For Flatpak feed installation and updates, add Flathub for the required runtime before
+installing SolidCraft; keep both remotes in the same user installation:
+
+```sh
+flatpak remote-add --user --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo
+flatpak remote-add --user --if-not-exists solvecraft https://bherbruck.github.io/solidcraft/flatpak/solvecraft.flatpakrepo
+flatpak install --user solvecraft ai.storyteller.solvecraft
+flatpak run ai.storyteller.solvecraft
+```
+
+Single-file `.flatpak` bundles include the runtime repository address; missing runtimes
+still need an internet connection. [Linux installation details](https://bherbruck.github.io/solidcraft/guide/getting-started.html#linux-flatpak).
+
 The builds aren't signed yet. On macOS, right-click `SolveCraft.app` in Applications and choose
 **Open** the first time (or run `xattr -dr com.apple.quarantine /Applications/SolveCraft.app`).
 On Windows, SmartScreen may say "Windows protected your PC": **More info**, then **Run anyway**.

.github/workflows/packaging-lint.yml

@@ -37,6 +37,10 @@ jobs:
         run: shellcheck packaging/*.sh packaging/*/*.sh packaging/linux/AppRun
       - name: Nightly release selection regression
         run: python3 packaging/tests/nightly_test.py
+      - name: Windows executable icon validation regression
+        run: python3 packaging/tests/windows_icon_test.py
+      - name: Flatpak desktop smoke validation regression
+        run: python3 packaging/tests/flatpak_test.py
       - name: PowerShell
         shell: pwsh
         run: |

.github/workflows/release.yml

@@ -177,7 +177,7 @@ jobs:
       - name: Install flatpak-builder
         run: |
           sudo apt-get update
-          sudo apt-get install -y --no-install-recommends flatpak flatpak-builder librsvg2-common
+          sudo apt-get install -y --no-install-recommends flatpak flatpak-builder librsvg2-common xvfb xauth weston dbus-x11
           # Ubuntu 24.04's AppArmor blocks the unprivileged user namespaces bubblewrap needs.
           sudo sysctl -w kernel.apparmor_restrict_unprivileged_userns=0
       - name: Build the Flatpak bundle