feat: generate icons as 16×16

[Repiteo]

Description

Converts all generated icons to a 16×16 format with pixel-perfect points, matching the updated contribution guidelines.

Contribution Guidelines

• By creating this pull request, I acknowledge that I have read the Contribution Guidelines for this project
• I have read the Code Of Conduct and promise to abide by these rules

[Repiteo]

The CL tools can't recognize generated files, so here's the svg outputs:

file

folder

folder-open

folder-root

folder-root-open

[PKief]

I could make out some differences between the normal folder icon and some specific folder icons (in this case the folder-dist icon). Then I put both of them together and found out that there's a different design. I'd highly appreciate if we could use the same folder shape for the default and the specific folder icons:

[Repiteo]

I agree with them being synced, but I'm not certain if that uniformity is actually enforced atm. It'd be nice if there was some way to explicitly sync these icons, but that might be outside the scope of this PR. I'll still look into it later today

[Repiteo]

Resynced the upper inconsistency for folders. However, I left the lower inconsitencies with the open folder deliberately, as it was previously lopsided so this is a "fix". However, if you want an exact match with (most) existing folders, then I think I'll just not bother with the folders at all — they couldn't really get anywhere close to pixel-perfect with their existing design

[PKief]

I'd prefer if all folder icons have the exact same shape. The rendering of the pixels will not work properly for these areas anyway. If only 16x16 pixels are available for rendering in low resolution, it only makes a difference if we fill the pixels completely. This can be clearly seen in our example from the Contribution Guidelines. Here you can clearly see that the lines that end directly with a pixel and thus fill an entire pixel have a very sharp edge.

"Consequently, when rendering a curve, we're essentially asking the display to render a fraction of a pixel, which is impossible. As a result, curves tend to appear blurry. This is normal. However, it's perfectly fine to use curves, circles, and rounded edges in your icons. Just keep in mind these limitations if you're wondering why your icon doesn't look as sharp as you'd like." (bullet point "Curves vs straight lines" in the contribution guidelines).

This is also the reason why the red areas in our folder will also never be perfect, regardless how the corners will be formed:

[Repiteo]

We'll roll with full parity then. The new commit is the original version downscaled by 50%, so they should match up perfectly with existing folders. I am interested in eventually revisiting my pixel-perfect implementation, but only if that could somehow be applied to all folders.