Fix missing commas in Kuzu graph INSERT queries

[Padarn]

Description

Fixed two missing commas in the Kuzu memory graph insertion queries:

1. Missing comma after source.mentions = 1 in ON CREATE SET clause (line 526)
2. Missing comma after source.mentions = coalesce(source.mentions, 0) + 1 in ON MATCH SET clause (line 529)

These syntax errors caused Kuzu parser exceptions when inserting entities with embeddings where the destination node exists but the source node is new.
Fixes # (issue)

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

I've added a unit test to the change

Please delete options that are not relevant.

• Unit Test

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• [x I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• [ x I have checked my code and corrected any misspellings

Maintainer Checklist

• closes #xxxx (Replace xxxx with the GitHub issue number)
• Made sure Checks passed

[CLAassistant]

All committers have signed the CLA.

[parshvadaftari]

@Padarn Can you please sign the CLA?

[parshvadaftari]

Can you explain why this is required?

[Padarn]

Thanks sorry I was testing this locally to make sure it was fixed, this can be removed

[Padarn]

Tests for scenario which bug was found in

[parshvadaftari]

Can you also provide me how to recreate this issue?

[Padarn]

If you run the unit test without the fix then you will get the error:

from my branch

git checkout main -- mem0/memory/kuzu_memory.py
python -m pytest tests/memory/test_kuzu.py::TestKuzu::test_kuzu -v

error

          RuntimeError: Parser exception: Invalid input <
                              source>: expected rule ku_Statements (line: 9, offset: 20)
          "                    source.embedding = CAST($source_embedding,'FLOAT[384]')"
                               ^^^^^^

test_env/lib/python3.13/site-packages/kuzu/connection.py:134: RuntimeError