fix idf path

Author: cgreening

.github/workflows/esp-idf-build.yml

@@ -47,7 +47,16 @@ jobs:
           CCACHE_DIR: /root/.ccache
         run: |
           set -euo pipefail
-          source /opt/esp/esp-idf/export.sh
+          # Location differs slightly across ESP-IDF container tags.
+          if [[ -f /opt/esp/idf/export.sh ]]; then
+            source /opt/esp/idf/export.sh
+          elif [[ -f /opt/esp/esp-idf/export.sh ]]; then
+            source /opt/esp/esp-idf/export.sh
+          else
+            echo "ERROR: ESP-IDF export.sh not found under /opt/esp"
+            ls -la /opt/esp || true
+            exit 1
+          fi
 
           echo "ESP-IDF version:"
           idf.py --version