[lint-monster] LintMonster: handle unchecked errors and discarded results (3,561 findings) #65472

Findings

The current make golint-custom run reports 3,561 unchecked or discarded results: 2,261 fmt.Fprintln errors, 1,196 fmt.Fprintf errors, 79 fmt.Fprint errors, 10 assignments discarding both results, 9 scanner loops that omit Err(), and 6 explicitly discarded Close() errors. Most findings are in pkg/cli (2,735) and pkg/workflow (734), with additional occurrences in pkg/console and pkg/parser.

Representative findings include unchecked formatting writes in pkg/console and pkg/workflow, plus scanner and close handling in pkg/parser and pkg/cli.

Remediation checklist

• Handle each reported error/result in a way that matches the surrounding function’s existing error flow; avoid silently dropping failures.
• Check scanner errors after loops and handle resource close errors where they affect the operation.
• Keep changes scoped to this diagnostic group and prefer minimal, targeted edits that preserve normal behavior.
• Run make golint-custom to validate the assigned findings.

Expected outcome: reported write, scan, cleanup, and discarded-result failures receive deliberate handling, and this diagnostic group is clean.