chore: import upstream snapshot with attribution

docker/devcontainer/docker-bake.hcl

@@ -0,0 +1,50 @@
+// Docker Bake configuration for freeCodeCamp devcontainer images
+//
+// Usage (from repo root):
+//   docker buildx bake -f docker/devcontainer/docker-bake.hcl          # Local build (native platform)
+//   docker buildx bake -f docker/devcontainer/docker-bake.hcl devcontainer --push  # Push multi-arch to GHCR
+//
+// With custom tag:
+//   TAG=v1.0.0 docker buildx bake -f docker/devcontainer/docker-bake.hcl devcontainer --push
+
+variable "REGISTRY" {
+  default = "ghcr.io/freecodecamp"
+}
+
+variable "TAG" {
+  default = "latest"
+}
+
+variable "TAG_LATEST" {
+  default = "true"
+}
+
+group "default" {
+  targets = ["local-devcontainer"]
+}
+
+target "_common" {
+  context    = "."
+  dockerfile = "docker/devcontainer/Dockerfile"
+}
+
+// Multi-arch image for pushing to registry (CI and local --push)
+target "devcontainer" {
+  inherits   = ["_common"]
+  target     = "devcontainer"
+  platforms  = ["linux/amd64", "linux/arm64"]
+  cache-from = ["type=gha"]
+  cache-to   = ["type=gha,mode=max"]
+  tags       = concat(
+    ["${REGISTRY}/devcontainer:${TAG}"],
+    TAG_LATEST == "true" ? ["${REGISTRY}/devcontainer:latest"] : []
+  )
+}
+
+// Native platform only (fast local builds)
+target "local-devcontainer" {
+  inherits = ["_common"]
+  target   = "devcontainer"
+  output   = ["type=docker"]
+  tags     = ["ghcr.io/freecodecamp/devcontainer:latest"]
+}