fix: replace global basicConfig with NullHandler

[Baho73]

Summary

• Replaces logging.basicConfig(filename="debug.log", level=logging.DEBUG) with logging.NullHandler()
• The basicConfig() call in logger.py overrides the root logger for any application that imports rosreestr2coord, silently redirecting all logs to a debug.log file
• NullHandler is the recommended approach for library logging in Python

Fixes #93

Before

import rosreestr2coord
# All application logs now go to debug.log instead of console

After

import rosreestr2coord
# Application logging is unaffected
# Users can configure rosreestr2coord logging explicitly if needed:
# logging.getLogger("rosreestr2coord").setLevel(logging.DEBUG)

Test plan

• Importing rosreestr2coord no longer creates debug.log
• Application logging remains unaffected after import
• Library internal logging still works when explicitly configured