ci: add synthetic fixture runner

ci/demo-build.sh

@@ -0,0 +1,55 @@
+#!/bin/sh
+set -eu
+mkdir -p reports artifacts
+rm -f reports/*.xml artifacts/*
+scenario=${SCENARIO:-success}
+version=${RELEASE_VERSION:-1.0.0}
+target=${TARGET_ENV:-sg}
+case "$scenario" in success|failure|unstable|aborted) ;; *) exit 2 ;; esac
+case "$target" in dev|staging|sg) ;; *) exit 2 ;; esac
+echo "[DEMO] Synthetic CI fixtures; no production deployment is performed."
+echo "[INFO] job=$JOB_NAME build=$BUILD_NUMBER scenario=$scenario target=$target version=$version"
+echo "[SCM] $(git log -1 --format='%h %s')"
+test -s README.md && test -s VERSION && test -s ci/demo-build.sh
+echo "[STAGE] checkout and configuration checks passed"
+lines=${LOG_LINES:-80}
+case "$lines" in ''|*[!0-9]*) exit 2 ;; esac
+[ "$lines" -le 3000 ] || exit 2
+i=1
+while [ "$i" -le "$lines" ]; do
+  if [ $((i % 37)) -eq 0 ]; then
+    printf '[WARN] Fixture retry checkpoint %04d: demo dependency responds slowly; retry budget remains.\n' "$i"
+  else
+    printf '[INFO] Checkpoint %04d: validate route, transform fixture, verify checksum and collect diagnostics.\n' "$i"
+  fi
+  i=$((i+1))
+done
+delay=${RUN_SECONDS:-2}
+case "$delay" in ''|*[!0-9]*) exit 2 ;; esac
+[ "$delay" -le 45 ] || exit 2
+sleep "$delay"
+failures=0
+[ "$scenario" != unstable ] || failures=2
+printf '<testsuite name="DemoContractTests" tests="12" failures="%s" errors="0" skipped="1" time="2.4">\n' "$failures" > reports/junit.xml
+i=1
+while [ "$i" -le 12 ]; do
+  printf '<testcase classname="demo.ContractSuite" name="case_%02d" time="0.2">' "$i" >> reports/junit.xml
+  if [ "$i" -eq 12 ]; then
+    printf '<skipped message="Optional demo scenario"/>' >> reports/junit.xml
+  elif [ "$failures" -gt 0 ] && [ "$i" -le 2 ]; then
+    printf '<failure message="Intentional demo assertion mismatch">Expected fixture validation success; scenario=unstable</failure>' >> reports/junit.xml
+    echo "[TEST-FAIL] case_$i intentional demo assertion mismatch"
+  fi
+  printf '</testcase>\n' >> reports/junit.xml
+  i=$((i+1))
+done
+printf '</testsuite>\n' >> reports/junit.xml
+printf 'Demo build\nJob: %s\nBuild: %s\nVersion: %s\nTarget: %s\nScenario: %s\n' "$JOB_NAME" "$BUILD_NUMBER" "$version" "$target" "$scenario" > artifacts/build-summary.txt
+printf '{"demo":true,"version":"%s","target":"%s","scenario":"%s"}\n' "$version" "$target" "$scenario" > artifacts/release-manifest.json
+tar -czf artifacts/demo-package.tgz README.md VERSION ci reports
+echo "[ARTIFACT] build-summary.txt release-manifest.json demo-package.tgz"
+if [ "$scenario" = failure ]; then
+  echo "[ERROR] Intentional demo packaging/configuration failure: invalid release fixture."
+  exit 1
+fi
+echo "[STAGE] Completed demo build; JUnit failures=$failures"