Merge build error messages and revert test snapshot changes
Build can't reliably distinguish Runtime from Dynamic causes, so
merge runtimeBodyMessage/dynamicBodyMessage into a single bodyMessage
(same for metadata and viewport). Reframe the fix list with
"the right fix depends on which API triggered this and what behavior
you want" instead of duplicating the next dev hint the framework
already provides below.
Revert all test snapshot changes to match canary — snapshots will be
updated in a follow-up once messages are finalized.
Made-with: Cursor
