Abstract file into class

[julesvirallinen]

Abstracts file to class, it can compile itself and return things.

Ideally it would handle it's own metadata too, and the compiler could be less complex.

Then we can do

type TCompiler = (PublishFile) => string

and inside a compiler:

const icon = publishFile.meta.getIcon 

instead of stuff like this:

		const noteIconKey = this.settings.noteIconKey;

		if (baseFrontMatter[noteIconKey] !== undefined) {
			publishedFrontMatter["noteIcon"] = baseFrontMatter[noteIconKey];
		} else {
			publishedFrontMatter["noteIcon"] = this.settings.defaultNoteIcon;
		}

It COULD be that we'd want PublishFile to extend TFile. Also not 100% on the name PublishFile.

[oleeskild]

I love this! This is a great abstraction.
I think it makes sense to not extend TFile, and instead keep it like it is now.
I can't think of a better name than PublishFile on the top of my head. It keeps the naming consistent, in that the obsidian API uses TFile. And I think it is easy to quickly grasp the concept when reading the code.

Could you rebase this on top of the current main branch? I'll merge it after.