feat(docker): add linux-arm64 reproducible build target

Cross-published via the existing x64 desktop image (self-contained
publish doesn't need ARM hardware), for Raspberry Pi and other
64-bit ARM boards.

docker/README.md

@@ -74,8 +74,9 @@ Running without arguments shows an interactive menu — pick a single target or
 Targets:
   windows     Win x64 single-file executable (native libs embedded)
   linux       Linux x64 single-file binary (runs as-is, nothing to install)
+  linux-arm64 Linux ARM64 single-file binary (runs as-is, nothing to install)
   android     Android APK (release-signed, prompts for keystore passwords)
-  all       All three targets
+  all         All targets above
 
 Options:
   --rebuild   Force rebuild of the Docker images (needed after editing a Dockerfile)
@@ -86,6 +87,7 @@ Examples:
 ```bash
 ./docker/build.sh all               # build everything
 ./docker/build.sh windows           # Windows only
+./docker/build.sh linux-arm64       # Linux ARM64 only
 ./docker/build.sh android --rebuild # Android, rebuilding the image first
 ```
 
@@ -97,9 +99,10 @@ All artifacts land in `dist/` at the repository root. The version number is
 read automatically from `<Version>` in `src/App/PalladiumWallet.App.csproj`.
 
 | Target      | Path                                                     |
-|---------|--------------------------------------------------|
+|-------------|-----------------------------------------------------------|
 | Windows     | `dist/windows/PalladiumWallet-{ver}-win-x64.exe`          |
 | Linux       | `dist/linux/PalladiumWallet-{ver}-linux-x64`              |
+| Linux ARM64 | `dist/linux-arm64/PalladiumWallet-{ver}-linux-arm64`      |
 | Android     | `dist/android/PalladiumWallet-{ver}.apk`                  |
 
 **Windows** — a single self-contained `.exe` (runtime and native libraries
@@ -119,6 +122,15 @@ effectively all of them); no .NET or other packages to install. If you
 transfer it through a channel that strips permissions (e.g. a web download),
 restore the execute bit with `chmod +x`.
 
+**Linux ARM64** — same as above, cross-published for `aarch64` (e.g.
+Raspberry Pi 4/5, ARM-based SBCs/laptops running a 64-bit distro). The build
+runs on an x64 Docker host — .NET's self-contained publish cross-targets
+`linux-arm64` without needing ARM hardware. Run it the same way:
+
+```bash
+./PalladiumWallet-{ver}-linux-arm64
+```
+
 **Android** — a release-signed APK for sideloading: transfer it to the phone
 and open it (enable "install from unknown sources" if prompted), or install
 via `adb install dist/android/PalladiumWallet-*.apk`. Supports Android 6.0+
@@ -138,7 +150,7 @@ via `adb install dist/android/PalladiumWallet-*.apk`. Supports Android 6.0+
 
 | Image               | Dockerfile           | Used for        | Size    |
 |---------------------|----------------------|-----------------|---------|
-| `plm-build-desktop` | `Dockerfile.desktop` | windows + linux | ~1.5 GB |
+| `plm-build-desktop` | `Dockerfile.desktop` | windows + linux + linux-arm64 | ~1.5 GB |
 | `plm-build-android` | `Dockerfile.android` | android         | ~5 GB   |
 
 Images are built automatically the first time a target needs them and reused

docker/build.sh

@@ -29,8 +29,9 @@ $(bold "Usage:") $(basename "$0") [TARGET] [OPTIONS]
 $(bold "Targets:")
   windows     Win x64 single-file executable  →  dist/windows/
   linux       Linux x64 single-file binary    →  dist/linux/
+  linux-arm64 Linux ARM64 single-file binary  →  dist/linux-arm64/
   android     Android APK (release-signed)    →  dist/android/
-  all       All three targets
+  all         All targets above
 
 $(bold "Options:")
   --rebuild   Force rebuild of Docker images (e.g. after Dockerfile change)
@@ -50,7 +51,7 @@ TARGET=""
 
 for arg in "$@"; do
     case "$arg" in
-        windows|linux|android|all) TARGET="$arg" ;;
+        windows|linux|linux-arm64|android|all) TARGET="$arg" ;;
         --rebuild)                             REBUILD=true ;;
         -h|--help)                              usage; exit 0 ;;
         *) err "Unknown argument: $arg"; usage; exit 1 ;;
@@ -62,10 +63,10 @@ if [[ -z "$TARGET" ]]; then
     bold "PalladiumWallet — reproducible build"
     echo ""
     PS3="Select target: "
-    options=("windows" "linux" "android" "all" "quit")
+    options=("windows" "linux" "linux-arm64" "android" "all" "quit")
     select opt in "${options[@]}"; do
         case "$opt" in
-            windows|linux|android|all) TARGET="$opt"; break ;;
+            windows|linux|linux-arm64|android|all) TARGET="$opt"; break ;;
             quit) echo "Aborted."; exit 0 ;;
             *) echo "Invalid choice, try again." ;;
         esac
@@ -172,6 +173,23 @@ build_linux() {
     ok "Linux → dist/linux/PalladiumWallet-${VERSION}-linux-x64"
 }
 
+build_linux_arm64() {
+    ensure_desktop_image
+    info "Building Linux ARM64 …"
+    run_build "$IMAGE_DESKTOP" \
+        "dotnet publish src/App.Desktop \
+            -r linux-arm64 \
+            -c Release \
+            -p:PublishSingleFile=true \
+            -p:IncludeNativeLibrariesForSelfExtract=true \
+            --self-contained \
+            -o /tmp/linux-arm64-out
+         install -m 755 /tmp/linux-arm64-out/PalladiumWallet \
+             \"/output/PalladiumWallet-${VERSION}-linux-arm64\"" \
+        "${DIST_DIR}/linux-arm64"
+    ok "Linux ARM64 → dist/linux-arm64/PalladiumWallet-${VERSION}-linux-arm64"
+}
+
 build_android() {
     ensure_android_image
 
@@ -223,10 +241,12 @@ START=$(date +%s)
 case "$TARGET" in
     windows)     build_windows     ;;
     linux)       build_linux       ;;
+    linux-arm64) build_linux_arm64 ;;
     android)     build_android     ;;
     all)
         build_windows
         build_linux
+        build_linux_arm64
         build_android
         ;;
 esac