chore: use changeset publish command

[artus9033]

Summary

This PR replaces npm publish with changeset publish to prevent:

➤ YN0035:   Response Code: 403 (Forbidden)
➤ YN0035:   Request Method: PUT
➤ YN0035:   Request URL: https://registry.yarnpkg.com/@callstack%2fbrownfield-cli
➤ YN0000: Failed with errors in 1s 732ms

e.g. on this run: https://github.com/callstack/react-native-brownfield/actions/runs/28857461435/job/85587457990

Test plan

CI green

[Copilot]

Pull request overview

This PR updates the monorepo’s release publishing step to use Changesets’ publishing flow instead of publishing every workspace directly, aligning the CI publish behavior with the repo’s existing Changesets-based versioning/release workflow.

Changes:

• Replace yarn workspaces foreach ... npm publish && changeset tag with changeset publish for CI publishing to avoid attempts to republish already-published versions.

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