Update .env for new server and agent image versions; enhance docker-compose.yml with dynamic agent names and extra hosts; add troubleshooting guide for port allocation issues.

TROUBLESHOOTING.md

@@ -0,0 +1,32 @@
+# Troubleshooting
+
+## Port 55432 Already Allocated (E2E Builds)
+
+**Symptom:**  
+A build step like "Postgres Up" fails with:
+
+```
+Bind for 0.0.0.0:55432 failed: port is already allocated
+```
+
+**Cause:**  
+A Postgres container from a previous build was not cleaned up properly (e.g. build failed before reaching its teardown step). Since all E2E builds use the same hardcoded host port `55432`, the stale container blocks any new build from starting.
+
+**Diagnosis:**
+
+```bash
+# Find what's holding the port
+docker ps --filter "publish=55432" --format "table {{.Names}}\t{{.Status}}\t{{.Ports}}"
+```
+
+**Fix:**
+
+```bash
+# Remove the stale container (replace the name with the one from the command above)
+docker rm -f <container-name>
+```
+
+Then re-run the failed build.
+
+**Prevention:**  
+Ensure every build configuration runs `docker compose down -v` in a cleanup/always-run step so containers are torn down even when earlier steps fail.