chore: init shared openfeature server provider

[joker23]

This PR will initialize the migration of openfeature node server provider to js-core. Specifically, this PR will create a shared openfeature server provider base class.

REVIEWER: The logic in this should be a more generalized version of https://github.com/launchdarkly/openfeature-node-server/tree/main.

Theoretically, this would allow us to implement openfeature providers pretty easily (eg https://github.com/launchdarkly/js-core/blob/skz/sdk-2213/openfeature-migration/packages/sdk/openfeature-node-server/src/LaunchDarklyProvider.ts)

NOTE: at the moment this code won't do anything until we implement the implementing provider in the next PR.

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Note

Low Risk
Low risk because this PR only adds a new, pre-release shared package and wiring (workspace/tsc/release-please) without changing behavior of existing SDKs. Main risk is limited to build/release configuration and the correctness of the new translation/provider utilities for future adopters.

Overview
Introduces a new pre-release workspace package, @launchdarkly/openfeature-js-server-common, exporting BaseOpenFeatureProvider plus utilities to translate OpenFeature evaluation contexts/results and tracking event details to LaunchDarkly equivalents.

Adds full package scaffolding (tsup/tsconfig/jest config, README/LICENSE, and unit tests) and wires it into the monorepo via package.json workspaces, root tsconfig references, and release-please manifest/config so it can be versioned and built independently.

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[github-actions]

@launchdarkly/js-sdk-common size report
This is the brotli compressed size of the ESM build.
Compressed size: 25623 bytes
Compressed size limit: 29000
Uncompressed size: 125843 bytes

[github-actions]

@launchdarkly/js-client-sdk size report
This is the brotli compressed size of the ESM build.
Compressed size: 31866 bytes
Compressed size limit: 34000
Uncompressed size: 113634 bytes

[github-actions]

@launchdarkly/browser size report
This is the brotli compressed size of the ESM build.
Compressed size: 179311 bytes
Compressed size limit: 200000
Uncompressed size: 830815 bytes

[github-actions]

@launchdarkly/js-client-sdk-common size report
This is the brotli compressed size of the ESM build.
Compressed size: 38473 bytes
Compressed size limit: 39000
Uncompressed size: 211104 bytes

[joker23]

@cursor review

[cursor]

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

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[cursor]

Prototype property lookup causes incorrect attribute rejection

Low Severity

The key in LDContextBuiltIns check uses the in operator, which traverses the prototype chain. This means context attributes named after Object.prototype properties (e.g., constructor, toString, valueOf) will incorrectly match, enter the type-validation branch, and be rejected with a confusing error message. The check against LDContextBuiltIns[key] would then return a function (the inherited method) rather than a type string, guaranteeing the typeof value === comparison fails. Using Object.hasOwn(LDContextBuiltIns, key) or Object.prototype.hasOwnProperty.call(LDContextBuiltIns, key) would fix this.

 

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