feat(src/renderer): unify fontgroup baseline

[takase1121]

This PR unifies font group baseline by choosing the max baseline value. This would be useful for the emoji PR.

Before:

After:

This can break stuff if your font has weird baselines, but it works in my case. I'd like to know if its bad or it should be a configurable value.

[takase1121]

VSCodium:

Foot:

[takase1121]

By averaging the baseline I got something like this:

[takase1121]

Now we align with the first font's baseline instead of calculating the min/max baseline. If you want the baseline of a certain script to be the dominant one, put the font for it as the first in a group. My hands are tied without parsing some OpenType tables and its ultimately up to personal preference as in how text should be vertically aligned.

This is the result:

It's relatively correct because CJK fonts don't have a baseline and should use centered alignment. JetBrains Mono aligns in the center, so it looks good.

This is the result with FiraSans, also looking good: