refactor: src and assets build tasks

.gitignore

assets/css/wpct7-theme.css

data.json

includes/fields/wpcf7/conditional/class-field.php

includes/integrations/wpcf7/class-integration.php

package-lock.json

package.json

src/js/ConditionalCheckbox.js

src/js/ConditionalControl.js

src/js/ConditionalHidden.js

src/js/ConditionalRadio.js

src/js/Form.js

src/js/gf.js

src/js/swv-conditional.js

src/js/wpcf7.js

wpct-erp-forms.php