Enhance TMP_ENV_FILE handling in 03_generate_secrets.sh

- Added a check to prevent duplicate entries when appending environment variables to TMP_ENV_FILE, ensuring cleaner and more efficient script execution.

scripts/03_generate_secrets.sh

@@ -464,7 +464,10 @@ fi
 # Add any custom variables that weren't found in the template
 for var in "FLOWISE_USERNAME" "DASHBOARD_USERNAME" "LETSENCRYPT_EMAIL" "RUN_N8N_IMPORT" "OPENAI_API_KEY" "PROMETHEUS_USERNAME" "SEARXNG_USERNAME" "LANGFUSE_INIT_USER_EMAIL" "N8N_WORKER_COUNT"; do
     if [[ ${found_vars["$var"]} -eq 0 && -v generated_values["$var"] ]]; then
-        echo "${var}=\"${generated_values[$var]}\"" >> "$TMP_ENV_FILE" # Ensure quoting
+        # Before appending, check if it's already in TMP_ENV_FILE to avoid duplicates
+        if ! grep -q -E "^${var}=" "$TMP_ENV_FILE"; then
+            echo "${var}=\"${generated_values[$var]}\"" >> "$TMP_ENV_FILE" # Ensure quoting
+        fi
     fi
 done