Add a differential package create flag

[andrewg-xyz]

Is your feature request related to a problem? Please describe

As I build and maintain uds-packages, I wish to optimize my ability to transfer updates in bandwidth-limited environments.

Describe the solution you'd like

• Given an update to a UDS-package bundle
• When running uds create . --differential (or similar)
• Then UDS will minimize the artifact size to a smaller footprint than the normal "full" bundle.

Additional context

Zarf has a similar flag --differential string [beta] Build a package that only contains the differential changes from local resources and differing remote resources from the specified previously built package

[UncleGedd]

@andrewg-xyz can we assume the uds create cmd is being run in an environment that is connected to a prod cluster?

[andrewg-xyz]

@UncleGedd you can not :( - I may build a bundle in my CI environment and airgap it to a CD environment. I believe you could assume previous versioned artifacts produced by uds create would be available.

[andrewg-xyz]

+1 Partner talked about a specific use case where they were limited to 1MB bandwidth when transferring "packages"

[UncleGedd]

cc @catsby