Adds a PostgreSQL partial unique index on (author, chapter, page) where all three fields are non-null, and returns HTTP 409 when a duplicate is detected. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Adds a PostgreSQL partial unique index on (author, chapter, page) where all three fields are non-null, and returns HTTP 409 when a duplicate is detected. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>