A simple addition to help me publish my book.

For now it convert Wikilinks [[my link]] to my Second Brain links ssp.sh/brain/my-link.

If I have a little time, I might update more, but for now, I can give a quick note about how I set it up:

1. I installed it through make build or make build-linux (It will run cargo build and move it to bin to execute )
2. I added this config to my book.toml:

[preprocessor.sspaeti]
command = "mdbook-sspaeti"
brain-base-url = "https://ssp.sh/brain" #link to website you want `[[my-link]]` point to. e.g. `https://ssp.sh/brain/my-link`
is-url-check = true #true ff you want to check if the links are valid. Will take some time

The preprocessor will automatically check on each run, if the links are valid and or not like this (might be a bit verbose each time..)

...
mdbook-sspaeti- check_link: The URL returned an ERROR: 404 Not Found, http://ssp.sh/brain/streaming-vs-batch-in-orchestration
mdbook-sspaeti- check_link: The URL is valid: http://ssp.sh/brain/semantic-layer
...

Hope that helps for now.