p5.sound's midiToFreq() allows microtonality (decimal MIDI notes)

### Most appropriate sub-area of p5.js?

- [ ] Accessibility
- [ ] Color
- [ ] Core/Environment/Rendering
- [ ] Data
- [ ] DOM
- [ ] Events
- [ ] Image
- [ ] IO
- [ ] Math
- [ ] Typography
- [ ] Utilities
- [ ] WebGL
- [ ] Build process
- [ ] Unit testing
- [ ] Internationalization
- [ ] Friendly errors
- [X] Other (specify if possible)

### p5.js version

1.11.1

### Web browser and version

Firefox 133.0.3

### Operating system

Windows 11

### Steps to reproduce this

### Steps:
1. Decimal numbers in midiToFreq() return microtonal values, because they're not rounded first.
2. This is actually a pretty cool feature, and allows some creative possibilites (microtonal music!), but it might be unexpected for some because [the reference](https://p5js.org/reference/p5/midiToFreq/) implies the value should be an integer MIDI note number:

> General MIDI treats notes as integers where middle C is 60, C# is 61, D is 62 etc. Useful for generating musical frequencies with oscillators.

Rather than 'fix' this, adding a note to the reference description along the lines of 'Decimal values return microtonal frequencies.' Might clarify that those values won't be rounded to equal temperament tuning, but keep a pretty cool, if unexpected, feature?

### Snippet:

```js

console.log(midiToFreq(60)); // returns 261.6255653005986 (Hz) = C4
console.log(midiToFreq(60.5)); // returns 269.2917795270241 = C4 quarter-sharp!
console.log(midiToFreq(61)); // returns 277.1826309768721 = C#4

```
I'd be happy to add this note to the reference if it's accepted.