Update date-fns to v4, migrate date-fns-tz to @date-fns/tz, use subpath imports

[Copilot]

Aligns date-fns usage with sanity-io/sanity: upgrade to v4, drop date-fns-tz for @date-fns/tz, and use subpath imports throughout.

@sanity/assist

• date-fns ^3.6.0 → ^4.1.0
• Barrel imports → subpath imports

@sanity/rich-date-input

• date-fns ^2.30.0 → ^4.1.0
• date-fns-tz removed, @date-fns/tz ^1.4.1 added
• formatInTimeZone(date, tz, fmt) → format(date, fmt, {in: tz(timezone)})
• getTimezoneOffset(tz, date) / 60 / 1000 → -new TZDate(date, tz).getTimezoneOffset()
• zonedTimeToUtc → helper using TZDate constructor (same pattern as sanity core's createTZDateFromComponents)

Lint

• Added date-fns barrel import restriction to .oxlintrc.json

-import {formatDistanceToNow} from 'date-fns'
+import {formatDistanceToNow} from 'date-fns/formatDistanceToNow'

-import {formatInTimeZone, getTimezoneOffset, zonedTimeToUtc} from 'date-fns-tz'
+import {tz, TZDate} from '@date-fns/tz'
+import {format} from 'date-fns/format'

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• sanity-cdn.com
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node node /home/REDACTED/work/plugins/plugins/dev/test-studio/node_modules/.bin/../sanity/bin/sanity build git conf�� -report-unused-disable-directives --global bin/node (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

Update all date-fns dependencies in the same way we did it on https://github.com/sanity-io/sanity which is where most of our date-fns code in this repo is originally from

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[changeset-bot]

🦋 Changeset detected

Latest commit: 4d7d9c1

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@sanity/assist	Patch
@sanity/rich-date-input	Patch

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Project	Deployment	Actions	Updated (UTC)
plugins-studio	Ready	Preview, Comment	Mar 6, 2026 2:09pm