MedEvac: per-record body field tokens

[morgang-adappt]

Description

Adds per-record body tokens for separate emails. A body field-select dropdown inserts {{Block N.field.path}} tokens, which the function then replaces with that row's value for each recipient. Nested paths are supported, and duplicate entries no longer accumulate in the body dataset field selector when the layout tab is reloaded.

Useful links

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• Please insert link to back-end branch if any
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Type of change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce.

• Test A
• Test B

Screenshots

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Checklist:

( * == Mandatory )

• * I have set myself as assignee of the pull request
• * My code follows the style guidelines of this project
• * Linting does not generate new warnings
• * I have performed a self-review of my own code
• * I have put the ticket for review, adding the oort-frontend team to the list of reviewers
• * I have commented my code, particularly in hard-to-understand areas
• * I have put JSDoc comment in all required places
• * My changes generate no new warnings
• * I have included screenshots describing my changes if relevant
• * I have selected labels in the Pull Request, according to the changes with code brings
• I have made corresponding changes to the documentation ( if required )
• I have added tests that prove my fix is effective or that my feature works
• * New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules