[Epic] Adopt @vuetify/v0 into Vuetify 4 through the minor line

[johnleider]

Tracking issue for adopting @vuetify/v0 into Vuetify core, slice by slice, through the 4.x minors.

Why this exists

The original plan put all v0 adoption in v5. That is short-sighted and would drag out the rollout — anything that translates safely without needing to be a breaking change should land on the minor line instead, and next should be reserved for genuinely major changes.

This issue is the public record of that work: what has landed, what is queued, and in which release. Each slice links to its PR as it merges.

Slices

#	Slice	Scope	Status
1	Utilities	Type guards, range, toHighlight	#23039 — open, milestone v4.2.0
2	Observers	useResizeObserver, useIntersectionObserver, useMutationObserver	Implemented on next as ec2fdbd (#22672) — to be moved to dev
3	Display / breakpoints	display composable	Implemented on next as d5fb1bf (#22710) — move to dev pending review
4	Registries	createRegistry and consumers	Not started
5	Selection	createSelection / createSingle / createGroup	Not started
6	Validation	createValidation, form field plumbing	Not started

Slices 4–6 are indicative, not committed; they will be firmed up as the earlier ones land.

Ground rules

• A slice lands on the minor line (dev → master) if it can translate without a breaking change. Only genuinely breaking work goes to next.
• Each slice is independently reviewable and independently shippable. No omnibus PRs.
• vuetify takes @vuetify/v0 as a real runtime dependency — no vendored copies or mirrored implementations.

Scope note

Adoption is incremental and public. As of #23039 the shipped surface is the utility layer only; composables and components follow through subsequent minors.