The merged-PR search was over-engineered and caused false negatives
(couldn't match PR to issue when title/body didn't contain #NNN).
Issue closed = dep satisfied. Factory only closes after merging.
Codeberg uses shared issue/PR numbering. When a PR IS the dep issue
(e.g. PR #665 fixes issue #665), the title search misses it.
Fallback checks if pulls/{dep_num} is merged.