fix: exclude angle brackets from bare URL match in validate-links

The bare absolute-URL regex stopped only at whitespace, `)`, and `"`. When
a `docs.seam.co/latest/...` URL appeared as anchor text inside HTML
(e.g. `>https://docs.seam.co/latest/foo</a></td>`), the match greedily
swallowed the trailing tags and reported the malformed path as broken.

Adding `<` and `>` to the exclusion set lets the bare URL pattern
terminate at the closing `<`, so cross-section absolute URLs in the
guides README validate cleanly.

Author: claude

codegen/validate-links.ts

@@ -13,7 +13,7 @@ function findSiteSection(filePath: string): SiteSection | undefined {
 }
 
 const absoluteUrlPattern = new RegExp(
-  `${baseUrl.replaceAll('.', '\\.')}[^)"\\s]+`,
+  `${baseUrl.replaceAll('.', '\\.')}[^)"<>\\s]+`,
   'g',
 )