chore: exclude maintainers from renovate automerge (#4698)

CODEOWNERS

@@ -1 +1,9 @@
+# ── CODEOWNERS ───────────────────────────────────────
 * @homarr-labs/maintainers
+
+# Exempt Renovate‑managed files (no owners)
+package.json          @none
+package-lock.json     @none
+pnpm-lock.yaml        @none
+Dockerfile            @none
+docker-compose.yml    @none