feat(marketing-site): American Dream cover band + narrative weave

- Cover: publisher-style belly band across the lower book cover using a
  compressed banner (2.2MB screenshot -> 60KB WebP, resized to display
  needs), cropped via a width-locked <img> + percentage offset so the
  wordmark stays legible rather than getting zoomed/cropped sideways.
  Compass + wordmark compacted into a row to make room.
- Copy: the theme woven through Field Notes, Contents, the Founding
  Sponsor tier, and one direct FAQ entry -- mostly oblique, since the
  cover already states it explicitly. Hero/Recipe/Capture/Footer left
  untouched on purpose.

marketing-site/components/FieldNotes.jsx

@@ -2,12 +2,12 @@ const NOTES = [
   {
     n: "01 / Stays current",
     h: "A subscription, not a static book",
-    p: "AI moves too fast for a book you buy once. Each annual edition is refreshed so the workflows still work when you open them.",
+    p: "AI moves too fast for a book you buy once. Each annual edition is refreshed so the ground you gain here doesn’t erode the moment you look away.",
   },
   {
     n: "02 / Authored, then open",
     h: "Written by practitioners first",
-    p: "The first edition is seeded by co-authors — a real founding library, not an empty shelf. Open, paid contribution opens once it’s worth browsing.",
+    p: "The first edition is seeded by co-authors — a real founding library, not an empty shelf. Open, paid contribution opens once it’s worth browsing, so the people who build it get to own a piece of it.",
   },
   {
     n: "03 / Responsible by design",