Fix hook z training reshape bug

[jbloomAus]

Description

Temporary solution to hook z reshaping bug in training described in #164. Checks if the sae is doing reshaping and if so turns it off during evals where we want to do reshaping ourselves. This is more a quick fix than an ideal long term solution as we should likely remove reshaping responsibilities from the SAE and make the caller provide the correct shaped object.

Fixes #164

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

Checklist:

• I have commented my code, particularly in hard-to-understand areas
• 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
• I have not rewritten tests relating to key interfaces which would affect backward compatibility

You have tested formatting, typing and unit tests (acceptance tests not currently in use)

• I have run make check-ci to check format and linting. (you can run make format to format code if needed.)