Comprehensive Guide

Although not the most complex, inc-complete is a somewhat involved library. It'd be nice if there were a comprehensive guide on how to use the library. There is a quick-start guide in the docs but a more thorough guide would be helpful covering topics such as:

- An in-depth walk through of inc-complete's algorithm
- How it is determined that a computation is up to date
- Input changed optimization to avoid traversing large graphs when no relevant inputs have changed
- Dealing with result types for which `Eq::eq` is expensive.
- `assume_changed` and its implications
- Serialization/deserialization practices
- Maintaining forwards compatibility
- What are computation IDs and the importance of keeping them stable for serialization
- Saving space in the final serialized artifact

etc.

Start with the existing quick-start guide in the docs and review the library’s algorithm and serialization/deserialization behavior. The guide should explain computation freshness, input-change optimization, expensive Eq::eq results, assume_changed, computation IDs, compatibility, and serialized artifact size.

Written by the indexing model from the issue text.