[Cloud Security] Feature Flag Support for Cloud Security Posture Plugin

[Omolola-Akinleye]

Summary

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Changes

• Adds enableExperimental to server configSchema
• Makes feature flags configurable via xpack.cloudSecurityPosture.enableExperimental in kibana.dev.yml
• Implements ExperimentFeatureService.get() for accessing feature flags
• Add passing initliaterContext to plugin in order to access our plugin config

Benefits

• Avoids circular dependency with Security Solution useIsExperimentalFeatureEnabled and prop drilling feature flags from Fleet plugin PackagePolicyReplaceDefineStepExtensionComponentProps
• Provides server-side configuration support
• Enables pre-release feature testing
• Creates centralized feature flag management

This allows controlled testing of new features before release through configuration rather than code changes.

[elasticmachine]

Pinging @elastic/kibana-cloud-security-posture (Team:Cloud Security)

[elasticmachine]

💔 Build Failed

• Buildkite Build
• Commit: a146bdf

Failed CI Steps

• Build Kibana Distribution
• Check Types

History

• 💔 Build #263859 failed fd2aaff

cc @Omolola-Akinleye