Forms System Rebuild - Zod Validation

Pain

Validation is inconsistent across the form layer. Some fields validate locally, some rely on ad hoc checks, and cross-field validation is effectively manual. That makes validation behaviour hard to predict, hard to test and hard for plugin or host application code to extend safely.

Approach

Introduce Zod-backed validation for all fields. Field-level validation, custom validators and cross-field rules are defined through one validation path so the form layer can report errors consistently regardless of field type or source.

Expected outcomes

• Every field type has a consistent validation path.
• Custom validation can be added without forking the form layer.
• Cross-field validation is supported as a first-class form capability.
• Validation errors are surfaced consistently in the editor UI.

Acceptance Criteria

• All built-in field types can run validation through Zod.
• Custom validators can be registered and composed with field validation.
• Cross-field validation can inspect sibling or form-level values.
• Validation errors surface consistently next to fields and in any form-level error summary.
• Validation runs at the expected lifecycle points: edit, blur and submit where appropriate.
• Tests cover valid input, invalid input, custom validation and cross-field validation.