Run margin generation within the main import pipeline

[hombit]

Feature request

I believe that margin generation should become more implicit and happen by default for every hipscat-import. I propose falling changes:

1. Generate margins with default 10'' margin_threshold within the "main" importing pipeline. This should be the default, however we still may allow a separate margin generation pipeline to a) generate more caches, b) split the pipeline for large/complicated imports.
2. Turn off fine filtering by default

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• I have described the purpose of the suggested change, specifying what I need the enhancement to accomplish, i.e. what problem it solves.
• I have included any relevant links, screenshots, environment information, and data relevant to implementing the requested feature, as well as pseudocode for how I want to access the new functionality.
• If I have ideas for how the new feature could be implemented, I have provided explanations and/or pseudocode and/or task lists for the steps.