feat: linux appimage build with docker, egl fallback, and webkitgtk fixes

Dockerfile.appimage

@@ -0,0 +1,81 @@
+FROM ubuntu:24.04
+
+ENV DEBIAN_FRONTEND=noninteractive
+
+# Tauri v2 build dependencies for Ubuntu 24.04 (glibc 2.39, WebKitGTK 2.44+)
+# Targets any distro from mid-2024 onwards while supporting modern Wayland compositors
+RUN apt-get update && apt-get install -y \
+    build-essential \
+    curl \
+    wget \
+    file \
+    libgtk-3-dev \
+    libwebkit2gtk-4.1-dev \
+    librsvg2-dev \
+    patchelf \
+    libssl-dev \
+    libayatana-appindicator3-dev \
+    libglib2.0-dev \
+    libgdk-pixbuf2.0-dev \
+    libsoup-3.0-dev \
+    libjavascriptcoregtk-4.1-dev \
+    xdg-utils \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install Node.js 22 LTS
+RUN curl -fsSL https://deb.nodesource.com/setup_22.x | bash - \
+    && apt-get install -y nodejs \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install Rust stable
+RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --profile minimal
+ENV PATH="/root/.cargo/bin:${PATH}"
+
+WORKDIR /app
+
+# Cache Rust dependencies first
+COPY src-tauri/Cargo.toml src-tauri/Cargo.lock src-tauri/
+COPY src-tauri/build.rs src-tauri/
+# Create stub lib/main so cargo can resolve the crate
+RUN mkdir -p src-tauri/src && \
+    echo 'fn main() {}' > src-tauri/src/main.rs && \
+    echo '' > src-tauri/src/lib.rs && \
+    cd src-tauri && cargo fetch && \
+    rm -rf src
+
+# Cache npm dependencies
+COPY package.json package-lock.json ./
+RUN npm ci
+
+# Copy the full source
+COPY . .
+
+# Build the AppImage
+RUN npx tauri build --bundles appimage
+
+# Strip GPU/GL libraries that linuxdeploy bundles from the build system.
+# These MUST come from the host's GPU driver at runtime  - bundling them causes
+# black windows, EGL failures, and driver mismatches on any system with a
+# different Mesa version or proprietary NVIDIA drivers.
+# See: https://github.com/AppImage/pkg2appimage/blob/master/excludelist
+RUN cd src-tauri/target/release/bundle/appimage && \
+    chmod +x *.AppImage && \
+    ./*.AppImage --appimage-extract && \
+    find squashfs-root \( \
+        -name "libEGL.so*" -o \
+        -name "libGL.so*" -o \
+        -name "libGLX.so*" -o \
+        -name "libGLdispatch.so*" -o \
+        -name "libOpenGL.so*" -o \
+        -name "libgbm.so*" -o \
+        -name "libdrm.so*" -o \
+        -name "libglapi.so*" -o \
+        -name "libGLESv2.so*" \
+    \) -delete && \
+    rm -f *.AppImage && \
+    wget -q https://github.com/AppImage/appimagetool/releases/download/continuous/appimagetool-x86_64.AppImage -O /tmp/appimagetool && \
+    chmod +x /tmp/appimagetool && \
+    ARCH=x86_64 /tmp/appimagetool --appimage-extract-and-run --no-appstream squashfs-root/ && \
+    rm -rf squashfs-root /tmp/appimagetool
+
+# The AppImage will be in src-tauri/target/release/bundle/appimage/