Make the examples more accessible

We have a lot of great examples, but they're probably not super helpful for people who are only learning the language. We often don't even link to any sources that people can use to read up on the methods used in those scripts.

We should flesh out their content to include many more literate blocks, that properly explain step by step the use case, and why Dex might be a good fit for it (showcase useful features, etc.).

Review the existing examples and their current explanatory text first. Expand the examples with step-by-step literate blocks, explain the use case and why Dex fits it, showcase useful features, and link to sources for the methods used; completion means the examples are more useful to language learners.

Written by the indexing model from the issue text.