fix: _get_all_from_vector_store by correctly handling 2D array check

[Seelly]

Description

Fix bug in _get_all_from_vector_store: Ensure correct handling of vector store result structure

when the memories_result is 2D array:[[]],there is an error

File "D:\Application\Anaconda3\envs\llm\Lib\site-packages\mem0\memory\main.py", line 580, in _get_all_from_vector_store
id=mem.id,
^^^^^^
AttributeError: 'list' object has no attribute 'id'

Fixes # (issue)

Type of change

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• [ - ] Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
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• Documentation update

How Has This Been Tested?

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• Unit Test
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Checklist:

• My code follows the style guidelines of this project
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• I have checked my code and corrected any misspellings

Maintainer Checklist

• closes #xxxx (Replace xxxx with the GitHub issue number)
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[AlinMH]

Hey, I have a similar fix #2795. Would you care to check if it's the same thing that we're trying to fix here?