Update dependency fastify-static to v4.2.4 [security]

Editor assessment

Updating fastify-static to v4.2.4 with the [security] marker tells the reader both what changed and why it mattered — a vulnerability-driven bump — which is real information compressed into the subject. The chore(deps) type and scope fit the maintenance change. No body follows, and for a security pin the marker plus version suffices, though naming the advisory would have added value. No footers appear. Hygiene is clean: imperative mood, no trailing period, precise subject, no pasted content. The message communicates the essentials of a security update in a single complete line.