feat: add webdav upload channel

deploy/worker/wrangler.toml

@@ -23,13 +23,6 @@ not_found_handling = "single-page-application"
 [vars]
 # TG_BOT_TOKEN = ""
 # TG_CHAT_ID = ""
-# Optional third-party WebDAV storage channel:
-# WEBDAV_BASE_URL = "https://dav.example.com/remote.php/dav/files/user/imgbed/"
-# WEBDAV_USERNAME = ""
-# WEBDAV_PASSWORD = ""
-# WEBDAV_PUBLIC_URL = ""
-# WEBDAV_HEADERS = "{\"X-Example\":\"value\"}"
-# WEBDAV_CREATE_DIRECTORY = "true"
 
 # [[d1_databases]]
 # binding = "img_d1"