feat: support waitForNetworkResults in FDv2 data manager

[kinyoklion]

The FDv2 data manager now respects the waitForNetworkResults identify option. When false (the default for mobile), identify resolves as soon as cached data is delivered rather than waiting for network.

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• I have added test coverage for new or changed functionality
• I have followed the repository's pull request submission guidelines
• I have validated my changes against all supported platform versions

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Note

Medium Risk
Changes when the identify promise resolves (cached-first vs network-fresh), which can alter initialization timing and app control flow across platforms.

Overview
FDv2DataManagerBase now respects LDIdentifyOptions.waitForNetworkResults by tracking a minimumDataAvailability threshold for identify completion.

When configured to not wait for network results, identify can resolve as soon as any initial data (e.g. cache) is delivered via dataCallback, while the data source continues initializing and applying subsequent updates as they arrive.

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[github-actions]

@launchdarkly/js-sdk-common size report
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Uncompressed size: 125843 bytes

[github-actions]

@launchdarkly/browser size report
This is the brotli compressed size of the ESM build.
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Uncompressed size: 830158 bytes

[github-actions]

@launchdarkly/js-client-sdk size report
This is the brotli compressed size of the ESM build.
Compressed size: 31722 bytes
Compressed size limit: 34000
Uncompressed size: 112975 bytes

[github-actions]

@launchdarkly/js-client-sdk-common size report
This is the brotli compressed size of the ESM build.
Compressed size: 37417 bytes
Compressed size limit: 38000
Uncompressed size: 205446 bytes

[kinyoklion]

bugbot review

[cursor]

✅ Bugbot reviewed your changes and found no new issues!

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