feat(ThemeProvider): add contextOnly prop to prevent rendering of wrapping div

[francinelucca]

Relates to https://github.com/github/primer/issues/6568

Seeing some issues in dotcom as a result of rendering the ThemeProvider div when switching from @primer/styled-react (no div) to @primer/react ThemeProvider. Adding opt-out mechanism via contextOnly prop.

Changelog

New

• Added a contextOnly prop to ThemeProviderProps and updated the implementation so that when contextOnly is true, the provider only supplies theme context without rendering a wrapping <div> with data-* attributes.
• Added comprehensive tests for the new contextOnly behavior, verifying both the absence of the wrapper <div> and that theme context is still provided to descendants.
• Added a no-op contextOnly prop to ThemeProviderProps for API compatibility with @primer/react, as documented in the prop's comment.

Rollout strategy

• Patch release
• Minor release
• Major release; if selected, include a written rollout or migration plan
• None; if selected, include a brief description as to why

Testing & Reviewing

Merge checklist

• Added/updated tests
• Added/updated documentation
• Added/updated previews (Storybook)
• Changes are SSR compatible
• Tested in Chrome
• Tested in Firefox
• Tested in Safari
• Tested in Edge
• (GitHub staff only) Integration tests pass at github/github-ui (Learn more about how to run integration tests)

[changeset-bot]

🦋 Changeset detected

Latest commit: 43b2c1c

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

This PR includes changesets to release 2 packages

Name	Type
@primer/styled-react	Minor
@primer/react	Minor

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[github-actions]

⚠️ Action required

👋 Hi, this pull request contains changes to the source code that github/github-ui depends on. If you are GitHub staff, test these changes with github/github-ui using the integration workflow. Check the integration testing docs for step-by-step instructions. Or, apply the integration-tests: skipped manually label to skip these checks.

To publish a canary release for integration testing, apply the Canary Release label to this PR.

[Copilot]

Pull request overview

Adds a contextOnly option to @primer/react’s ThemeProvider so consumers can opt out of the extra wrapping <div> (while still receiving theme context), aligning migration ergonomics from @primer/styled-react.

Changes:

• Added contextOnly?: boolean to ThemeProviderProps and updated ThemeProvider rendering behavior when enabled.
• Added unit tests asserting wrapper <div> presence/absence and that theme context remains available when contextOnly is set.
• Updated package-lock.json entries to reflect @primer/react version 38.25.0 as referenced by workspace/example package manifests.

Show a summary per file

File	Description
packages/styled-react/src/components/ThemeProvider.tsx	Adds a no-op contextOnly prop for API compatibility with @primer/react.
packages/react/src/ThemeProvider.tsx	Implements contextOnly behavior by skipping the wrapper <div> and only rendering the context provider.
packages/react/src/tests/ThemeProvider.test.tsx	Adds test coverage for the new contextOnly behavior.
package-lock.json	Updates lockfile to reflect @primer/react version 38.25.0 references.

Copilot's findings

• Files reviewed: 3/4 changed files
• Comments generated: 1

[primer-integration]

👋 Hi from github/github-ui! Your integration PR is ready: https://github.com/github/github-ui/pull/21854

[primer-integration]

Integration test results from github/github-ui:

  CI Passed
  VRT Passed
  Projects Passed

All checks passed!