feat(12.1-02): password and form-only fields, rules per operation and preset

- pact.FormVirtualFields lists form fields that are not model columns: never
  bound, filled or projected; their values reach the Form hooks through
  cabana.VirtualFieldsFromContext when the field's context allows the operation
- type: password is a masked field that must be listed as virtual
- pact.FormRules supplies the rule set per operation and replaces the model's
  Rules() for admin saves; a rule on a virtual field sees the submitted value
- preset on a text field follows another text field on the create form
- SPA: PasswordField, preset handling in FormView, empty password left out of
  an update
- README, docs, OpenAPI document, TS types and dist updated

modules/phrasebook/backend/lang/en/lang.yaml

@@ -68,6 +68,8 @@ form:
   create: Create
   return_to_list: Back to list
   return_to_preview: Back to preview
+  show_password: Show password
+  hide_password: Hide password
   close: Close
   confirm: Confirm
   saving: Saving…