chore: remove Source Code section from product landing pages

The GitHub repository links are not needed on the public-facing
hooks documentation pages.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: zackkatz

templates/hooks/product-index.md

@@ -27,7 +27,3 @@ Actions allow you to run custom code at specific points during {{label}}'s execu
 Filters allow you to modify data as it passes through {{label}}.
 
 {{/hasFilters}}
-## Source Code
-
-The source code for {{label}} is available on GitHub:
-- [GitHub Repository](https://github.com/{{repo}})