fix: add explicit styles for welcome tab

[jarekdanielak]

Closes #4555

Proposed Changes

Welcome tab now always looks the same, even if you open and close some diagrams.

Checklist

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• Brief textual description of the changes present
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• Related issue linked via Closes {LINK_TO_ISSUE} or Related to {LINK_TO_ISSUE}

[jarekdanielak]

The root cause of this issue are carbon styles user in variable outline. There is no simple way to scope them without some hacking (thanks @marstamm), so I'll stick with explicit styles on the side of welcome page.

I realized there is no need to introduce new class as I can just reuse tab__name for welcome page too. Having p font-size defined explicitly doesn't seem like a hack for me. We want the font on this page to be this size, so it might as well say it in the styles.

[nikku]

Great root causing on this issue! What we can see is that the carbon normalization (that is lazy loaded!) has many effects, and will always override whatever we normalize in the modeler.

What I propose is that we tackle this in an orderly manner as part of #4511, which I've moved to ready.

Before

After

Root cause

(Again, Carbon "normalization"):

[nikku]

For now I pushed a bunch of additional fixes:

• e375843 => We not only fix font-size, but also paragraph styles.
• 0f4a4ad => We fix custom toggle formatting
• 196c6b0 => We fix line height in all UI heavy components

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Some screenshots (fixed, broken in Camunda Modeler v5.28.0) attached:

[nikku]

Ready to be merged from my end (#4599 (comment)).

[lmbateman]

Not sure I have anything constructive to add, except maybe that the radio buttons in the Deploy popup look very odd (at least on my machine). Many thanks to Nico for looping me in and helping me to understand the line height issues.

[nikku]

@lmbateman Let's verify on tomorrows nightly if they look odd still. Should be fixed with this PR.

[barmac]

Still reproducible:

[nikku]

Yea. Was merged to main, pending integration into develop, which is done now.

Fixed in tomorrows nightly 🙃, or on develop:

[barmac]

Confirmed: