New and updated docs for build parallelism, optimal Dockerfiles, and Depot Cache

Our new build parallelism guide explains how stage-level parallelism and multi-platform builds work and includes a decision matrix to help you choose between autoscaling, larger builders, or separate projects.

We added new guides to our optimal Dockerfiles collection for popular package managers across Node.js, Python, Java, .NET, PHP, Rust, Ruby, and Go. Each example demonstrates how to use BuildKit cache mounts to significantly speed up your builds.

Our Depot Cache reference documentation now includes instructions for using Depot Cache with container builds via depot/build-push-action for Bazel, Go, Gradle, Maven, moonrepo, Pants, sccache, and Turborepo.