fix(ci): update environment variable checks and enhance staging configuration

Correct the regex in the Docker deployment workflow to properly validate environment variable placeholders. Additionally, update the staging environment configuration by adding specific keys and values for Tencent Cloud services, ensuring proper setup for deployment.

.github/workflows/docker-build-deploy.yml

@@ -308,7 +308,7 @@ jobs:
             exit 1
           fi
           # 仅检查「有效配置行」：跳过整行注释，避免 # KEY=your_* 示例误伤部署
-          if grep -Ev '^[[:space:]]*#' "$ENV_SRC" | grep -Eq '=(your_|replace_with_|\\.{3})$'; then
+          if grep -Ev '^[[:space:]]*#' "$ENV_SRC" | grep -Eq '=(your_|replace_with_|\.{3}$)'; then
             echo "::error::$ENV_SRC 仍包含占位符值，请先完善环境文件。"
             exit 1
           fi