Add OCI image labels, .dockerignore, and GH Actions Dependabot tracking

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: midwan

.dockerignore

@@ -0,0 +1,21 @@
+# VCS / GitHub metadata — not part of any build
+.git
+.gitignore
+.github
+.dockerignore
+
+# Repo docs / licensing — not COPY'd into the image
+*.md
+LICENSE
+
+# OS / editor noise
+.DS_Store
+Thumbs.db
+*.swp
+*~
+.vscode
+.idea
+
+# Local artifacts
+*.log
+*.bak

.github/dependabot.yml

@@ -5,7 +5,11 @@
 
 version: 2
 updates:
-  - package-ecosystem: "docker" # See documentation for possible values
-    directory: "/" # Location of package manifests
+  - package-ecosystem: "docker" # base image versions in Dockerfile
+    directory: "/"
+    schedule:
+      interval: "weekly"
+  - package-ecosystem: "github-actions" # actions/checkout, docker/build-push-action, etc.
+    directory: "/"
     schedule:
       interval: "weekly"

Dockerfile

@@ -17,8 +17,11 @@ ARG sdl3_ref
 ARG sdl3_image_repo
 ARG sdl3_image_ref
 
-LABEL maintainer="Dimitris Panokostas"
-LABEL description="Image with the requirements to cross-compile Amiberry for Debian AARCH64 (ARM64)"
+LABEL org.opencontainers.image.title="Amiberry build environment (Debian aarch64)"
+LABEL org.opencontainers.image.description="Image with the requirements to cross-compile Amiberry for Debian AARCH64 (ARM64)"
+LABEL org.opencontainers.image.authors="Dimitris Panokostas"
+LABEL org.opencontainers.image.source="https://github.com/BlitterStudio/amiberry-docker-aarch64"
+LABEL org.opencontainers.image.licenses="GPL-3.0"
 
 RUN dpkg --add-architecture arm64 && \
     apt-get update && \