feat: make the initial value template generation optional

[Jamiewarb]

Currently there is no way to opt-out of the initial value template generation, and instead they need to be removed if not being used.

This commit adds a configuration option to opt-out of either the static, parametized or both template generation.

By default, both are still generated.

initialValueTemplates: false will prevent any generation initialValueTemplates: 'static' will only generate the static templates initialValueTemplates: 'parameterized' will only generate the parameterized templates