Better quality of life in add entry UI

[mlell]

It might be just my taste, but for my uses the new entry UI has some papercuts:

• Payee field is large and narration field is small, despite my payees are seldom more than 3 words and the narration is long
• Metadata value fields are very short. I keep things there like the original narration (like it is on my bank statement => long) or a merged string of all SEPA identifiers
• Buttons disappear on mouse hover, which makes it unusable for touch screen users.

This PR fixes that, I have added before/after screencasts below:

Before:

Bildschirmaufzeichnung.vom.2025-12-17.16-21-20.mp4

After:

Bildschirmaufzeichnung.vom.2025-12-17.16-22-18.mp4

[yagebu]

Thanks for the PR!

[yagebu]

This tilts the balance too far in the other direction IMHO. This now leads to most of my payees being cut off

[mlell]

Changed to flex-grow: 2,

Before:

After:

[yagebu]

@mlell I've made some more wide-ranging refactors to these components and incorporated your improvements as well in #2169, can you take a look at that one?

[yagebu]

Thanks, these changes have been applied with #2169