ci: add container build workflow

Add prebuilt build images and a publish workflow to speed CI by reusing heavy dependencies.

packages/containers/tauri-linux/Dockerfile

@@ -0,0 +1,12 @@
+ARG REGISTRY=ghcr.io/anomalyco
+FROM ${REGISTRY}/build/rust:24.04
+
+ARG DEBIAN_FRONTEND=noninteractive
+
+RUN apt-get update \
+  && apt-get install -y --no-install-recommends \
+    libappindicator3-dev \
+    libwebkit2gtk-4.1-dev \
+    librsvg2-dev \
+    patchelf \
+  && rm -rf /var/lib/apt/lists/*