fix: Detector order

[sidharthv96]

📑 Summary

Rearrange detectors so that diagrams are properly detected.

Resolves flowchart-elk not being detected

📏 Design Decisions

Diagrams with more specific detectors should come on top of the list.

eg, when matching flowchart-elk from diagram text, if flowchart detector is checked before flowchart-elk's detector, the diagram would incorrectly be detected as flowchart.

So, we need to check flowchart-elk first. Same case with -v2 diagrams.

📋 Tasks

Make sure you

• 📖 have read the contribution guidelines
• 💻 have added unit/e2e tests (if appropriate)
• 📓 have added documentation (if appropriate)
• 🔖 targeted develop branch

[aloisklink]

I'm not super experienced with the whole registerLazyLoadedDiagrams code, but so far, it looks good to me!

By the way, is it also worth making the detectors for flowchart and stateDiagram stricter (maybe all other diagrams too)?

E.g. checking for /flowchart\s/ (must end with a white-space character)

I'm guessing that:

```mermaid
stateDiagram-blah-blah-blah
    [*] --> Still
    Still --> [*]

    Still --> Moving
    Moving --> Still
    Moving --> Crash
    Crash --> [*]
```

should probably throw a unrecognized diagram error, instead of the current error.

After all, somebody might make a custom flowchart-v100 diagram type as a plugin, and I believe that then their external usage of registerLazyLoadedDiagrams() would be called after we've already called registerLazyLoadedDiagrams() internally.

[sidharthv96]

By the way, is it also worth making the detectors for flowchart and stateDiagram stricter (maybe all other diagrams too)?

Making it stricter now might break many existing diagrams. So I'd prefer we don't mess with that.

[aloisklink]

Making it stricter now might break many existing diagrams.

It won't for the stateDiagram diagrams at least, since right now, trying to render a diagram that starts with stateDiagram-blah-blah-blah means that the stateDiagram jison parser throws an error, so it's not too big of a deal if we change it to a no diagrams detected error.

It's probably something that's low priority, so it shouldn't go in this PR.

[MermaidChart]

Look great, thanks @sidharthv96 !