[DT-2578] Convert darFormUtils.js to TypeScript

[kevinmarete]

Addresses

https://broadworkbench.atlassian.net/browse/DT-2578

Summary

This PR migrates darFormUtils.js and related files to Typescript.

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[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
5.2% Duplication on New Code

See analysis details on SonarQube Cloud