Update environment variable loading to allow overrides

- Modified load_dotenv() calls in multiple files to include override=True, ensuring that .env variables can replace existing environment variables.
- Updated ota_storage.py to use default values for OTA upload directories, improving clarity and maintainability.
- Enhanced get_ota_upload_dir() function to read environment variables dynamically, ensuring accurate directory paths based on the current environment.

backend/ota_storage.py

@@ -16,13 +16,9 @@ OTA_MODEL_X8 = "Luxsin-X8"
 OTA_MODEL_X9 = "Luxsin-X9"
 OTA_UPLOAD_MODELS = {OTA_MODEL_X8, OTA_MODEL_X9}
 
-# 本地根目录；实际文件路径为 {根}/{md5前5位}/LUXSIN.PKG
-OTA_UPLOAD_DIR_DEV = os.getenv(
-    "OTA_UPLOAD_DIR_DEV", "H:/soft/projects/luxsin/dashboard/ota"
-)
-OTA_UPLOAD_DIR_PROD = os.getenv(
-    "OTA_UPLOAD_DIR_PROD", "/data/project/dashboard/upload"
-)
+# 默认本地根目录；实际路径为 {根}/{md5前5位}/LUXSIN.PKG（具体目录在 get_ota_upload_dir 内按当前环境读取）
+_OTA_UPLOAD_DIR_DEV_DEFAULT = "H:/soft/projects/luxsin/dashboard/ota"
+_OTA_UPLOAD_DIR_PROD_DEFAULT = "/data/project/dashboard/upload"
 
 AWS_REGION = os.getenv("AWS_REGION", "eu-central-1")
 AWS_ACCESS_KEY_ID = os.getenv("AWS_ACCESS_KEY_ID", "")
@@ -39,8 +35,12 @@ OTA_FILENAME_X9 = "LUXSIN.PKG"
 
 
 def get_ota_upload_dir() -> Path:
-    is_dev = os.getenv("DEBUG", "False").lower() in ("true", "1", "yes")
-    raw = OTA_UPLOAD_DIR_DEV if is_dev else OTA_UPLOAD_DIR_PROD
+    """按 DEBUG 选开发/生产目录；每次调用重新读环境变量，避免 import 早于 load_dotenv。"""
+    debug_val = (os.getenv("DEBUG") or "false").strip().lower()
+    is_dev = debug_val in ("true", "1", "yes", "on")
+    dev = os.getenv("OTA_UPLOAD_DIR_DEV", _OTA_UPLOAD_DIR_DEV_DEFAULT)
+    prod = os.getenv("OTA_UPLOAD_DIR_PROD", _OTA_UPLOAD_DIR_PROD_DEFAULT)
+    raw = dev if is_dev else prod
     return Path(raw)