fix: render non-task list items in tree

[ilandikov]

Types of changes

Done by pairing with @claremacrae

Changes visible to users:

• Bug fix (prefix: fix - non-breaking change which fixes an issue)
• Documentation (prefix: docs - improvements to any documentation content for users)
• Sample vault (prefix: vault - improvements to the Tasks-Demo sample vault)

Internal changes:

• Tests (prefix: test - additions and improvements to unit tests and the smoke tests)

Description

• some progress on addressing 'show tree' does not render non-task checkboxes #3170
• ListItem now optionally stores a status character

Motivation and Context

• see 'show tree' does not render non-task checkboxes #3170

How has this been tested?

• unit tests

Screenshots

With this markdown - and a global filter #task:

-  [ ] #task task parent
    - [ ] #task task child
    - [ ] non-task child
    - list item child

```tasks
filename includes {{query.file.filename}}
show tree
```

Checklist

• My code follows the code style of this project and passes yarn run lint.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• My change has adequate Unit Test coverage.

Terms

• My contribution follows this project's contributing guide
• I agree to follow this project's Code of Conduct

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud