Misc improvements to the docs

[Zac-HD]

• Suggest using @composite instead of data() where possible, a pet peeve of mine
• Note that max_examples can go way up from the default; see Weighting of emoji in text strategies? #1401
• Explicitly note that builds() handles dataclasses as well as attrs classes
• Generally expand the docs on stateful testing, closes Improve documentation of stateful testing #1190

[Zac-HD]

Year to date, we've averaged 33/36 releases per day! 🚀