Fix resume health-check failure by adding required \lastupdated metadata

[Copilot]

The health-check Actions job was failing because resume/resume.tex did not define the \lastupdated command expected by the workflow parser. This PR adds the missing metadata in the required format so the freshness check can evaluate age correctly.

• Root cause addressed

  • resume-health-check.yml enforces presence of \newcommand{\lastupdated}{YYYY-MM-DD} and fails hard if missing.

• Minimal code change

  • Added a single LaTeX command in resume/resume.tex:

    \newcommand{\lastupdated}{2026-07-01}

  • No workflow logic or unrelated resume content was modified.

• Impact

  • Restores compatibility with the existing CI freshness gate by providing the exact token the check regex requires.