feat: Add table name to default index name

[duwenxin99]

Add table name as prefix to default index name upon index creation to avoid conflicting default index names for different tables.

1. Change DEFAULT_INDEX_NAME to DEFAULT_INDEX_NAME_SUFFIX.
2. Change index_name default in the BaseIndex class to None.
3. In aapply_vector_index(), check if the index_name field is None and if so, give it a default index name (table_name + DEFAULT_INDEX_NAME_SUFFIX).

[conventional-commit-lint-gcf]

🤖 I detect that the PR title and the commit message differ and there's only one commit. To use the PR title for the commit history, you can use Github's automerge feature with squashing, or use automerge label. Good luck human!

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