ci: remove develop branch from docs deployment trigger

Only deploy docs when pushing to main branch to avoid duplicate runs
when merging develop into main.

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

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

Author: brooksyang

.github/workflows/deploy-docs.yml

@@ -4,7 +4,6 @@ on:
   push:
     branches:
       - main
-      - develop
     paths:
       - 'docs/**'
       - '.github/workflows/deploy-docs.yml'