insights: shorten landing page header text and make POV consistently second person

Created by: Joelkw

cc @AlicjaSuska would like your signoff on this copy change. I wanted to make the title shorter and change the words, make it about "your" code, and emphasize "customizable" is about the metrics more than about the dashboards.

I believe it will look like this:

cc @vovakulikov or @justin my \u2014 was an attempt at inserting an emdash. It should be an emdash, not a single -, which is too short and not the correct punctuation (minor, but while I was fixing anyway!)

Test plan

Not setup to deploy locally at the moment – can someone check the emdash? Otherwise can catch on k8s.