- Replace the per-tool format invocations with treefmt (devenv's treefmt-nix integration): Ruby via syntax_tree, SQL via sqlfluff, configured in devenv.nix. - Exclude sqlfluff's LT05 (line too long) so `sqlfluff format` exits 0 as a formatter; the long lines it can't wrap no longer fail it. - Point app:format and the Claude on-save hook at treefmt (SQL now formats on save too), drop the Rakefile format task, and update AGENTS.md.