feat: Don't convert primary thumbnail to byte array

[lukeblevins]

Resolved / Related Issues

• Related Discussion: Investigate the fetching of unneeded byte array per storage item #6089

Details of Changes

• Removes unneeded reliance on thumbnail byte array for remaining app surfaces
• Switches away from glyphs as icons of items with unloaded extended properties

Validation
How did you test these changes?

• Built and ran the app
• Tested the changes for accessibility

Screenshots (optional)
N/A

[lukeblevins]

@yaichenbaum and I did some testing and it's a mixed bag:

1.) This change didn't yield a very large improvement in thumbnail load times. In fact, they were mostly comparable across the two versions
2.) It did, however, reduce memory usage by 35% during the particularly synthetic scenario where one loads a large directory and scrolls every item into the viewport (That amounted to 200MB for 4620 items in System32)
3.) CPU usage was lower (-5%), but not consistently less enough to be significant

I think we should go ahead with this change after I fix the Properties dialog thumbnails, but I'll let this sit for some more input

[yaira2]

@duke7553 I think it makes sense to continue with this and hopefully we can include it in one of the next preview builds. For the meantime, do you think you can add back the wireframe placeholder icon until we get a change to come up with a proper alternative?

[d2dyno1]

Is this still relevant?

[d2dyno1]

Ok! I was just checking on if any work is still being made.

[yaira2]

Great work!