chore: migrating current react features

[joker23]

This PR copies the react features that are in https://github.com/launchdarkly/react-client-sdk/blob/main/.sdk_metadata.json to the new js-core react sdk met.

NOTE: there will be another PR to add in features that are supported in the new sdk (if any)

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Note

Low Risk
Low risk metadata-only change, but incorrect feature/version mappings could mislead tooling or documentation that consumes this file.

Overview
Updates .sdk_metadata.json to replace the React SDK’s single contexts feature entry with a full, versioned feature matrix (for example allFlags, bootstrapping, secureMode, hooks, and others), aligning React metadata with the upstream React client SDK feature list.

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[github-actions]

@launchdarkly/js-sdk-common size report
This is the brotli compressed size of the ESM build.
Compressed size: 25661 bytes
Compressed size limit: 29000
Uncompressed size: 126143 bytes

[github-actions]

@launchdarkly/browser size report
This is the brotli compressed size of the ESM build.
Compressed size: 179253 bytes
Compressed size limit: 200000
Uncompressed size: 828804 bytes

[github-actions]

@launchdarkly/js-client-sdk-common size report
This is the brotli compressed size of the ESM build.
Compressed size: 37015 bytes
Compressed size limit: 38000
Uncompressed size: 202741 bytes

[github-actions]

@launchdarkly/js-client-sdk size report
This is the brotli compressed size of the ESM build.
Compressed size: 31446 bytes
Compressed size limit: 34000
Uncompressed size: 111621 bytes

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Feature versions reference wrong SDK's version history

Medium Severity

The introduced version numbers (e.g., "2.9", "3.0", "3.8") are from the old launchdarkly-react-client-sdk package, but this metadata entry is for the new @launchdarkly/react-sdk which has only had versions 0.0.1, 0.1.0, and 0.1.1. Every other SDK in this file has introduced versions within its own actual version range. The previous value "contexts": { "introduced": "0.0.1" } was correct for this package. Any tooling using these version numbers to determine feature availability would conclude that the current SDK supports zero features, since all introduced versions exceed 0.1.1.