add scheduled run for wire fuzzing workflow

[GianIac]

If you'd like to help with Numax, this is a great place to start, thank you so much for taking a look !

Add a scheduled trigger to the wire fuzzing workflow so it runs periodically, not only on push/PR/manual dispatch.

Why

• fuzzing gains value from continuous background execution
• scheduled runs can catch regressions outside active PR windows
• this is a small, isolated CI improvement

Scope

• update .github/workflows/fuzz.yml
• add a schedule trigger with a reasonable cron cadence
• keep existing push/pull_request/workflow_dispatch behavior intact

Done when

• the fuzz workflow includes a scheduled trigger
• existing fuzz jobs/targets remain unchanged
• documentation is updated if needed to reflect scheduled fuzzing

Notes

Please prefer a conservative schedule that is useful but not noisy.

Thanks again for considering contributing to Numax.