add password authentication for bot users

assistant_bot/config.py

@@ -10,6 +10,7 @@ PROJECT_ROOT = Path(__file__).resolve().parent.parent
 ENV_FILE = PROJECT_ROOT / ".env"
 
 TOKEN_ENV_NAME = "BOT_TOKEN"
+PASSWORD_ENV_NAME = "ASSISTANT_PASSWORD"
 DB_ENV_NAME = "ASSISTANT_DB"
 MODE_ENV_NAME = "ASSISTANT_MODE"
 OLLAMA_BASE_URL_ENV_NAME = "OLLAMA_BASE_URL"
@@ -80,6 +81,16 @@ def get_bot_token() -> str:
     return token
 
 
+def get_assistant_password() -> str:
+    load_env_file()
+    password = os.getenv(PASSWORD_ENV_NAME, "").strip()
+    if not password:
+        raise RuntimeError(
+            f"Set {PASSWORD_ENV_NAME} in environment or .env file."
+        )
+    return password
+
+
 def get_db_path() -> Path:
     load_env_file()
     raw_path = os.getenv(DB_ENV_NAME)