chore: release 0.3.28

[cafitac]

Summary

• fix agent-learner update to prefer the npm executable next to the installed wrapper script before falling back to the active node or plain npm
• add a regression test for login/non-interactive shells where the wrapper script lives under nvm but node resolves from another PATH entry
• release version 0.3.28 so the wrapper fix is available as a deployed artifact

Test Plan

• node --test test/wrapper.test.cjs --test-name-pattern='runWrapperUpdate prefers the npm next to the wrapper script when node comes from a different PATH entry'
• npm test
• PYTHONPATH=src .venv/bin/python -m pytest -q
• reproduced current published 0.3.27 failure: agent-learner update used /usr/local/bin/npm and hit EACCES on /usr/local/lib/node_modules/@cafitac