align file and folder permissions

[crazy-max]

• fixes The Builds menu in docker desktop is not available for-mac#7454
• fixes Docker Desktop: Builders Application error for-mac#7356
• fixes Internal Server Error for-mac#7277
• fixes Internal server error when running docker for-mac#7362
• fixes Application Error We've reported this to our error tracker. Internal Server Error for-mac#7195
• fixes Docker Build - Internal Server Error - Application Issue Report for-mac#7144
• fixes (Docker desktop) Can't access to some pages anymore due to an Application error: "Internal server error" for-mac#7186
• fixes Docker Desktp > Docker Builds Showing Application Error / Images are not Building  for-mac#7309

When invoking docker with sudo the owner will not be the one from user space and therefore some files and folders in buildx config might not be accessible by other tools (on macos sudo keeps user home dir). This affects reading current builder, last activity for a builder or local state. This change aligns file and folder permissions. Similar to how image id and metadata file are currently created:

• buildx/commands/build.go

  Line 377 in 1de3325

  if err := os.WriteFile(options.imageIDFile, []byte(getImageID(resp.ExporterResponse)), 0644); err != nil {

• buildx/commands/build.go

  Line 745 in 1de3325

  return ioutils.AtomicWriteFile(filename, b, 0644)

And same with cli when creating context: https://github.com/docker/cli/blob/31eeed7ca4c951ede2d18c73e4bd47e8189be221/cli/context/store/metadatastore.go#L43

This will avoid permissions issues reported on Docker Desktop when opening the build view on macos.