RFC: determine best practices for field and form validation

There are a lot of outstanding questions regarding:
- what validations to apply to different fields
- what validations to appy to a form as a whole
- when to trigger validations and show errors

A lot of these questions were asked in [`#11837`](https://app.zenhub.com/workspaces/entities-team-space-6143567664fb320019b81f39/issues/bcgov/entity/11837) and others are being mulled over by @severinbeauvais , @yuisotozaki , @tlebedovich, @rkim13103 , @forgeuxGH5 et al.

This ticket is to answer and document the answers so as to provide best practises for design and implementation from this point forward. (See also [`#11922`](https://app.zenhub.com/workspaces/design-team-space-6144b1bb15dbac0013e68828/issues/bcgov/entity/11922) for design considerations.)

#### Validation mechanisms

- [vuetify-mask](https://www.npmjs.com/package/vuetify-mask)
- [v-mask](https://www.npmjs.com/package/v-mask)
- [forms](https://vuetifyjs.com/en/components/forms/)
- [input components](https://vuetifyjs.com/en/api/v-input/#props)
- [vuelidate/schema](https://github.com/vuelidate/vuelidate)
- business logic (eg, need at least X directors) (higher level than component itself but part of overall filing requirements)
- _add others here_

Start by reviewing the questions in #11837 and the design considerations in #11922, then compare the listed mechanisms: vuetify-mask, v-mask, forms, input components, Vuelidate/schema, and business logic. Done means the outstanding field, form-level, and validation-timing questions are answered and the resulting best practices are documented for future design and implementation.

Written by the indexing model from the issue text.