add chroot env package download timing, optimize ubuntu minimal raw user template

[samueltaripin]

Merge Checklist

All boxes should be checked before merging the PR

• [/ ] The changes in the PR have been built and tested
• [/ ] Documentation has been updated to reflect the changes (or no doc update needed)
• [/ ] Ready to merge

Description

1. add chroot env package download timing
2. optimize ubuntu minimal raw template

Any Newly Introduced Dependencies

How Has This Been Tested?

new build timing for ubuntu minimal raw in TGL NUC
Build:

Rebuild:

[Copilot]

Pull request overview

This PR adds timing instrumentation for chroot environment package downloads so the CLI can report that phase separately, and updates the Ubuntu 24.04 minimal raw example template to a more explicit/bootable raw layout.

Changes:

• Add a new “Chroot Package Download” timing stage, plumbed from providers → chroot builder → CLI timing display.
• Extend ImageTemplate with chroot package download timing fields and adjust stage-gap calculations accordingly.
• Update ubuntu24-x86_64-minimal-raw.yml with a concrete disk layout, EFI grub bootloader config, and package set adjustments.

Reviewed changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
internal/utils/display/display.go	Adds new timing stage to the build timing table output.
internal/utils/display/display_test.go	Updates timing table tests for the new stage/parameters.
internal/config/config.go	Tracks chroot package download duration and adjusts derived timing gaps.
internal/chroot/chrootenv.go	Plumbs the build template into the chroot environment/builder.
internal/chroot/chrootbuild/chrootbuild.go	Stores build template and finishes the chroot download timer after package download.
internal/provider/azl/azl.go	Passes the build template to the chroot env before initialization (for timing).
internal/provider/elxr/elxr.go	Same as above for ELXR provider.
internal/provider/emt/emt.go	Same as above for EMT provider.
internal/provider/rcd/rcd.go	Same as above for RCD provider.
internal/provider/ubuntu/ubuntu.go	Same as above for Ubuntu provider.
cmd/os-image-composer/build.go	Includes the new chroot package download duration in timing display.
internal/provider/azl/azl_test.go	Mock formatting adjustment to satisfy interface usage in tests.
internal/provider/elxr/elxr_test.go	Mock formatting adjustment to satisfy interface usage in tests.
internal/provider/rcd/rcd_test.go	Mock formatting adjustment to satisfy interface usage in tests.
internal/provider/ubuntu/ubuntu_test.go	Mock formatting adjustment to satisfy interface usage in tests.
internal/image/isomaker/isomaker_test.go	Minor mock comment/formatting adjustment.
internal/image/imageos/imageos_test.go	Mock formatting adjustment to satisfy interface usage in tests.
image-templates/ubuntu24-x86_64-minimal-raw.yml	Reworks the Ubuntu minimal raw template with explicit disk + bootloader + packages.

Comments suppressed due to low confidence (1)

internal/utils/display/display_test.go:138

• The hidden-stage assertions are currently coupled to the table formatting (e.g., searching for "| Package Download "), which makes the test brittle if spacing/formatting changes. Prefer asserting on the stage labels themselves (e.g., "Package Download", "Image Conversion") rather than including the pipe/padding.

	hiddenStages := []string{"| Package Download ", "| Image Conversion "}
	for _, stage := range hiddenStages {
		if strings.Contains(logs, stage) {
			t.Fatalf("expected zero-duration stage %q to be hidden", stage)
		}