ui: Remove padding from icons

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This removes padding from icons so they’ll be sized consistently, see the results in the preview. It started off just being about the inconsistency in alignment of the pencil icon here in the chat session menu, where it looked like this:

Now:

I used SVG Crop to crop the icons. I looked at using svgo-autocrop and svg-autocrop but neither worked because of mysterious Puppeteer problems, it didn’t seem worth the added complexity, but it does mean that we have to manually ensure new icons don’t have padding.

I’ve adjusted the use of icons to make things look the same but there are slight differences!

For the special case where there’s a “crossed out” version (realm write permissions), I added icon-pencil-not-crossed-out which is icon-pencil-crossed-out with the crossing-out stroke hidden, the pencil is slightly smaller to allow for the stroke to cover it.

[github-actions]

Test Results

586 tests  ±0   582 ✔️ ±0   8m 34s ⏱️ +31s
    1 suites ±0       4 💤 ±0 
    1 files   ±0       0 ❌ ±0 

Results for commit 0db24ab. ± Comparison against base commit c220289.

♻️ This comment has been updated with latest results.

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Thanks for checking this out, @lukemelia, I kept it in draft because the size change has cascading effects, did you see the Percy diffs?

IconX similarly has padding around its edge. Should we standardise on not having that padding except in cases like the crossed-out-ness needing it?