Add Rust Markdown parser tutorial

[rita3ko]

To do:

• Get it running 😅
• Add missing images

[kristianfreeman]

lgtm!

[adamschwartz]

I’d like to see us take a pass at making it a bit more consistent with the other tutorials. For example how we handle prereqs and also using code block frontmatter for filenames, etc.

[adamschwartz]

Please see suggested changes below. I expanded on my previous comment with some links to the Docs Engine docs which hopefully makes things a bit clearer!

[adamschwartz]

Let’s add a "Before you start" section here, like we do in the other tutorials:

import TutorialsBeforeYouStart from "../../_partials/_tutorials-before-you-start.md"

# Build a Markdown parser with Rust and WebAssembly

<TutorialsBeforeYouStart/>

<!-- ... -->

(Note: “parser” also lowercased.)

[adamschwartz]

“Parser” → “parser”

[adamschwartz]

Prefix line with at least $. See https://docs-engine-docs.adam.workers.dev/markdown#terminals for examples. If it’s a series of steps requiring a specific set of directors, prefix with ~/ $ to start and then after e.g. cd-ing into rustwasm-markdown-parser, prefix with ~/rustwasm-markdown-parser $ etc.

[adamschwartz]

Per previous, should be:

~/rustwasm-markdown-parser $ wrangler dev

Since it’s required that you be in the project directory for wrangler dev to work.

[adamschwartz]

Must be on separate lines for parsing:

<Aside>

The first time you run `wrangler dev` might take a couple minutes to compile to WebAssembly. 

</Aside>

See https://docs-engine-docs.adam.workers.dev/markdown#asides

[adamschwartz]

Use filenames feature (see https://docs-engine-docs.adam.workers.dev/markdown#filenames):

```toml
---
filename: Cargo.toml
---
[dependencies]
pulldown-cmark = "0.4.0"
```

[adamschwartz]

Use filenames feature of code blocks (see https://docs-engine-docs.adam.workers.dev/markdown#filenames).

[adamschwartz]

~/rustwasm-markdown-parser $ wrangler build

[adamschwartz]

~/rustwasm-markdown-parser $ wrangler dev