emoji: Ensure consistent row height for plain text emoji theme.

[yash-agarwa-l]

Fixes #1587

Fix vertical layout shift in plain-text emoji picker by enforcing 44px minimum row height to match icon-based rows.

Before

Default

Plain Text

After

Default

Plain Text

[chrisbobbe]

CI is failing; I recommend running tools/check locally and fixing the issues it finds.

[yash-agarwa-l]

I ran tools/check locally and all checks/tests pass on my end.
Please let me know if there’s anything else I should adjust.

Thanks!

[yash-agarwa-l]

I've rebased on the latest main branch to pick up the dependency fixes.
CI is now passing.