fix(renovate): the workflow still named renovate.json, so every run since #79 died with ENOENT

#79 renamed the config to renovate.json5 and left configurationFile pointing at the old
name. Runs 315-322 (2026-10-22..29) all failed in ~1s before Renovate started.

Also add a ci/lint.sh assertion that every workflow configurationFile: resolves to a real
path — valid YAML, so yamllint could not catch it, and the gate stayed green throughout.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

ci/lint.sh

@@ -27,3 +27,18 @@ fi
 
 yamllint -c "${CI_DIR}/yamllint.yaml" -f "${YAMLLINT_FORMAT:-standard}" "${files[@]}"
 ok "yaml/lint passed (${#files[@]} files)"
+
+# A workflow's `configurationFile:` must name a file that exists. Renovate's did not after #79
+# renamed renovate.json -> renovate.json5, and every scheduled run failed with ENOENT for 11 days
+# while the gate stayed green. Valid YAML, so yamllint cannot see it.
+missing=0
+while IFS=: read -r wf _ value; do
+  value="${value#*configurationFile:}"
+  value="$(echo "$value" | sed -E 's/#.*//; s/^[[:space:]"'\'']+//; s/[[:space:]"'\'']+$//')"
+  if [ -n "$value" ] && [ ! -e "$value" ]; then
+    err "${wf}: configurationFile '${value}' does not exist in the repo"
+    missing=1
+  fi
+done < <(grep -nE '^[[:space:]]*configurationFile:' .gitea/workflows/*.y*ml 2>/dev/null || true)
+[ "$missing" -eq 0 ] || exit 1
+ok "workflow configurationFile references resolve"