Remove --model from at least some of the vector enrich-text examples

[Westwooo]

When the enrich-text examples were written the model had to be passed in, since it could not be specified any other way. Now that the model is provided through the config file we can remove the model flag from most, if not all, of the examples.

[ldoguin]

It could make sense to use 2 different models though. Because you could pipe the result of one model to another. Like asking an LLM and pipe it to a local, specialized SML.