Configure golangci-lint v2.12.2 with a curated linter set (bodyclose, errorlint, gocritic, gosec, revive, etc.) plus gofumpt + goimports formatters. Add a GitHub Actions workflow that runs lint on push and PR. Tune rule suppressions for CLI idioms (tablewriter result discard, PAGER subprocess, urfave/cli int casts, proto Id/Url naming). Apply golangci-lint --fix across 59 files for whitespace, gofumpt, and staticcheck rewrites; tests still pass.