Feature/107183 add ability to right align tree items description

[trapgar]

Issue #107183: Add a new right-aligned "description" property to TreeItems

Added the ability for VS Code extensions utilizing the TreeView to horizontally align the description property of TreeItems to the right. Default value remains left-aligned.

How to Test

1. Clone the vscode-extension-samples project

2. Open the tree-view-sample in Code

3. Open src/nodeDependencies.ts#

4. Add a new line right below where the TreeItem.description is being set

   this.alignment = 'right';`

   (since the repo references a released version of the vscode api you will want to also add an // @ts-ignore right about it just for testing)

5. Run the extension as usual

6. Open any repo utilizing npm (I just created a new folder and ran > npm i three

7. Click on the new list clover in the left-hand sidebar that the extension added

8. Expand the tree and all the package versions will now be aligned to the right

Since TreeItem actions appear to the right, the description will hide any-time they show as to not clash.

[trapgar]

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[alexr00]

Thank you for the PR! We're about to start our endgame. I'll take a close look at this PR once we branch for release at the end of next week.

[alexr00]

I think we want to allow extension authors to set a description (left aligned) and a second description (right aligned) instead of just the one description which we allow extension authors to set the alignment of. Not sure about a good name for this "second description". Maybe detail?

[trapgar]

Ah, understood. I'm assuming the styling (apart from the alignment) should mimic that of the description? e.g.: font/size/color/etc.

[trapgar]

@alexr00 Hi, can I get clarification on how we want this to function?

In this image, you can see that long text has the potential to hide or clash with the left-aligned text (all the TreeItems in the picture have both description and detail set, the label and description is just hidden when the right-aligned text overlaps).

In terms of styling, I also assume we want a different colouring/etc?