Set logger stacklevel (flagos-ai#1113)

### PR Category
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Hardware | CICD | Tools | Others ] -->
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### PR Types
<!-- One of [ User Experience | New Features | Bug Fixes | Improvements
| Performance | Breaking Change| Deprecations | Test Case | Docs |
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Improvements
### PR Description
<!-- Describe what you’ve done -->
Fix the logger stacklevel to point to the real location of the function
e.g.
before: 
[2026-02-09 19:51:00,204 FlagScale logger.py:25 INFO]
after:
[2026-02-10 11:58:06,728 FlagScale inference_qwen_gr00t.py:50 INFO]

Author: legitnull

flagscale/logger.py

@@ -22,19 +22,19 @@ def __init__(self, name, level=logging.INFO):
         self.logger.addHandler(stream_handler)
 
     def info(self, message):
-        self.logger.info(message)
+        self.logger.info(message, stacklevel=2)
 
     def warning(self, message):
-        self.logger.warning(message)
+        self.logger.warning(message, stacklevel=2)
 
     def error(self, message):
-        self.logger.error(message)
+        self.logger.error(message, stacklevel=2)
 
     def critical(self, message):
-        self.logger.critical(message)
+        self.logger.critical(message, stacklevel=2)
 
     def debug(self, message):
-        self.logger.debug(message)
+        self.logger.debug(message, stacklevel=2)
 
 
 GLOBAL_LOGGER = None