fix(coding-agent): release v0.4.2 - #325

Summary

Release Diffex v0.4.2 from the merged owner-requested changelog audit in #324.

Reasoning

This patch release contains the goal-mode additions, context compaction and recall improvements, user-directed subagent delegation, and reliability fixes documented in the audited changelogs.
Promote the exact generated release and next-cycle commits through a merge commit so the existing release tag remains an ancestor of protected main.
Push the tag only after the release source is verified on remote main.

Changes

• Bump all 18 workspace versions and 23 internal dependency requirements from 0.4.1 to 0.4.2.
• Regenerate root and example lockfiles, CLI shrinkwrap, and installation locks with version-only changes.
• Date all nine audited changelog sections and add fresh Unreleased sections in a separate next-cycle commit.
• Preserve external dependency versions, dependency graphs, and integrity values.
• Preserve the owner's original worktree and local AGENTS.md edits.

Testing

• Pre-bump candidate passed isolated npm, pnpm, and Bun imports, terminal fixtures, and installation/update/uninstall acceptance.
• Real ChatGPT gpt-6-luna returned ok in print and interactive modes from both npm- and Bun-installed CLIs outside the repository.
• Release preparation ran once from synchronized main at ed867434a.
• Release model-data hydration and validation, generated-lock checks, and npm run check passed.
• npm run build:offline and the full isolated ./scripts/test.sh suite passed.
• Reviewed all 34 release outputs; semantic validation confirmed only version fields, internal dependency requirements, the CLI tarball URL, and dated changelog headings changed.
• No release tag has been pushed.