Display up to 2 decimal places for bpm in timing screen metronome

[minetoblend]

Addresses part of #31263

Displays the bpm value in the metronome with up to 2 decimal places.
While interpolating, the value will be displayed as an integer, since going between 2 integer bpm values looks kinda jank otherwise. Once the value is within 1 bpm of the target value it will display the final value with up to 2 decimal places.

Screen.Recording.2025-01-20.at.00.50.08.mov

For comparison, here's the jankiness that would result from not applying the rounding.

Screen.Recording.2025-01-20.at.01.08.28.mov

[peppy]

Dunno. Metronomes usually are not accurate to decimal points. I'd personally say that the physical metronome should round to int still.

But if this is seen as a breaking usability concern then 🤷

[minetoblend]

If the metronome was less prominent I'd probably agree. However, given that

• The actual text box for the bpm is off-screen by default
• It moves & makes sounds so it draws extra attention

makes the metronome extremely prominent on the timing screen and displaying everything rounded to the nearest integer just conveys incorrect information.

Since the timing point rows only display one decimal place, does showing just one decimal sound like a compromise here? While having timing points that require 2 decimal places is not very common, having values that end in 0.5 is common enough to warrant the extra precision imo.

[peppy]

Made some changes.

Of note, this now displays more precision than other places in the editor. Which is weird, but needs to be addressed elsewhere if at all.