Add Aliyun SDK dependencies and implement TTL configuration for ECS instances

- Added new dependencies for Aliyun ECS SDK in requirements.txt and setup.py to support instance management features.
- Introduced a new config module to handle TTL settings for ECS instances, allowing for auto-termination based on environment variables.
- Updated the manager to utilize TTL settings, including scheduling instance termination with proper error handling and logging.
- Maintained existing code logic while enhancing functionality for improved instance lifecycle management.

desktop_env/providers/aliyun/config.py

@@ -0,0 +1,31 @@
+import os
+
+
+# Default TTL minutes for instance auto-release (Aliyun-side)
+# Can be overridden via environment variable DEFAULT_TTL_MINUTES
+# ATTENTION: ECS requires TTL to be at least 30 minutes (if TTL > 0)
+MIN_TTL_MINUTES: int = 30
+
+_ttl_env_str = os.getenv("DEFAULT_TTL_MINUTES", "60")
+try:
+    _ttl_env_val = int(_ttl_env_str)
+except Exception:
+    _ttl_env_val = 60
+
+# If TTL is positive but less than Aliyun minimum, clamp to 30 minutes
+if _ttl_env_val > 0 and _ttl_env_val < MIN_TTL_MINUTES:
+    DEFAULT_TTL_MINUTES: int = MIN_TTL_MINUTES
+else:
+    DEFAULT_TTL_MINUTES: int = _ttl_env_val
+
+# Master switch for TTL feature
+ENABLE_TTL: bool = os.getenv("ENABLE_TTL", "true").lower() == "true"
+
+
+def compute_ttl_seconds(ttl_minutes: int) -> int:
+    try:
+        return max(0, int(ttl_minutes) * 60)
+    except Exception:
+        return 0
+
+