Making the progress bar of title extractor unified

[AstraBert]

Description

This PR makes the progress bar of TitleExtractor unified for all title extractions jobs instead of one per job.

Fixes #19129

New Package?

Did I fill in the tool.llamahub section in the pyproject.toml and provide a detailed README.md for my new integration or package?

• Yes
• No

Version Bump?

Did I bump the version in the pyproject.toml file of the package I am updating? (Except for the llama-index-core package)

• Yes
• No

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)
• This change requires a documentation update

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Suggested Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added Google Colab support for the newly added notebooks.
• 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
• I ran uv run make format; uv run make lint to appease the lint gods

[logan-markewich]

technically this will run all title extractions sequentially per node instead of previously concurrently (I think)

Did we want to keep run_jobs but just disable progress since its a nested run_jobs call?

[AstraBert]

I don't know about sequentially vs concurrently, because in theory (from what I could see up to now) we still run one node per call of the function, so it should not make a great performance difference (?)
But I don't have a strong opinion of this, really, so we can also keep things as they were disabling the show_progress :))

[logan-markewich]

Ah I see what you mean. Yes technically no change in performance here from old->new