feat: restructure unstructured for local upload

[nboyse]

Signed-off-by: DBT pre-commit check

Context

Unstructured really struggles locally with documents being processed

What

• Removes auto strategy being inferred allt he time
• Image heavy have hi res config specified explicitly
• Page split properly for image heavy
• Dont infer tables on image heavy docs
• Less retries as they just overload cpu

Have you written unit tests?

• Yes
• No (add why you have not)

Are there any specific instructions on how to test this change?

• Yes (if so provide more detail)
• No

Relevant links

[github-actions]

⚠️ Python Vulnerabilities detected: 8 unique issues.

High:

• CVE-2025-64439 (fix: 3.0.0, severity: HIGH, GHSA: GHSA-wwqv-p2pp-99h5)
• CVE-2026-23490 (fix: 0.6.2, severity: HIGH, GHSA: GHSA-63vm-454h-vhhq)
• CVE-2026-24486 (fix: 0.0.22, severity: HIGH, GHSA: GHSA-wp53-j4wj-2cfg)
• CVE-2025-30167 (fix: 5.8.1, severity: HIGH, GHSA: GHSA-33p9-3p43-82vq)
• CVE-2025-53000 (fix: , severity: HIGH, GHSA: GHSA-xm59-rqc7-hhvf)

Moderate:

• CVE-2026-21860 (fix: 3.1.5, severity: MODERATE, GHSA: GHSA-87hc-h4r5-73f7)

Unknown (to be checked):

• CVE-2025-67221 (fix: , severity: UNKNOWN)
• CVE-2026-0994 (fix: , severity: UNKNOWN)

[github-actions]

Your PR has commits that are missing the Signed-off-by trailer. This is likely due to the pre-commit hook not being configured on your local machine. The usual fix for this issue is to run pre-commit install --install-hooks --overwrite -t commit-msg -t pre-commit, however for more detailed help in setting up the pre-commit hooks, follow the instructions at https://github.com/uktrade/github-standards/blob/main/README.md#usage