fix: validate-metadata-required-for-on-all-entities

[Zaimwa9]

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Changes

Closes #6520

Includes a refactor of the logic in order to prepare #6620

• Simplified AddMetadataToEntity component
• Created mergeMetadataFields and metadataValidation in a utils + unit tests
• Added validation for both update and create for environments and features
• ⚠️ NB: disabled state for segments has not been implemented as it is on a different page (could be confusing) and error from api is well handled

How did you test this code?

• New unit tests
• Create metadata fields in organisation (at least 2 required for each of them)
• Go to create feature / update feature / create environment / update environment / segments and play around

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Project	Deployment	Actions	Updated (UTC)
flagsmith-frontend-preview	Ready	Preview, Comment	Feb 24, 2026 4:40pm
flagsmith-frontend-staging	Ready	Preview, Comment	Feb 24, 2026 4:40pm

1 Skipped Deployment

Project	Deployment	Actions	Updated (UTC)
docs	Ignored	Preview	Feb 24, 2026 4:40pm

[github-actions]

Docker builds report

Image	Build Status	Security report
ghcr.io/flagsmith/flagsmith-api-test:pr-6658	Finished ✅	Skipped
ghcr.io/flagsmith/flagsmith-e2e:pr-6658	Finished ✅	Skipped
ghcr.io/flagsmith/flagsmith-api:pr-6658	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith-private-cloud:pr-6658	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith:pr-6658	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith-frontend:pr-6658	Finished ✅	Results ✅

[talissoncosta]

Looks good, just some non blocking comments

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Cursor Bugbot has reviewed your changes and found 2 potential issues.

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