Bracketed-name fields shown as .null by docs

[Lyrth]

Environment

name	version
IDEA version	IdeaIU 2020.3
Luanalysis version	1.2.1-IDEA203
OS	Win7

What are the steps to reproduce this issue?

1. Create a class/shape with bracketed field names, e.g.:
   
2. With the sample shape above, try to index members (and assign to them) through an instance of the class/shape, through brackets or dot notation (if possible), then hover over the indexer (example in "What happens?" section)
3. Additionally, type a. on a new line and look at the suggestions.

What happens?

2: Bracketed fields show as .null


(Field m is correct when hovered, both by doing a.m and a["m"]: shows Test.m)

3: The bracketed fields aren't being suggested

What were you expecting to happen?

For 2, should show the field names normally: treating the n field as Test.n, and others as Test[1], Test[true], etc.
For 3, it should at least include n; better if it'd also suggest the non-string-name fields.

Any logs, error output, etc?

None

Any other comments?

Also, field description is placed too near to the left edge of the tooltip, don't know if it's normal.

[Benjamin-Dobell]

The primary issue identified is resolved by 2a48c29

I've opened a separate issue (#28) to track completion of (primitive) indexed field.