The Rails schema dumper can't capture CREATE FUNCTION statements, so every
db:schema:dump silently drops the execute <<~SQL block that defines
f_unaccent, breaking schema loading downstream (the functional GIN
indexes reference the missing function).
Mirror the existing schema-load enhance hook with a post-dump task that
re-injects the block between the last enable_extension and the first
create_table. Idempotent: skips when the block is already present.
Also bundle the merge-upstream skill that documents the recurring merge
patterns for this fork.
