Fix text-wrapping on Safari (#1980)

Co-authored-by: Alex Alex@dytry.ch

closes [#1978](https://github.com/tldraw/tldraw/issues/1978)

Text was wrapping on Safari because the measure text div was rendered
differently on different browsers. Interestingly, when forcing the
text-measure div to be visible and on-screen in Chrome, the same
text-wrapping behaviour was apparent. By setting white-space to 'pre'
when width hasn't been set by the user, we can ensure that only line
breaks the user has inputted are rendered by default on all browsers.

### Change Type

- [x] `patch` — Bug fix
- [ ] `minor` — New feature
- [ ] `major` — Breaking change
- [ ] `dependencies` — Changes to package dependencies[^1]
- [ ] `documentation` — Changes to the documentation only[^2]
- [ ] `tests` — Changes to any test code only[^2]
- [ ] `internal` — Any other changes that don't affect the published
package[^2]
- [ ] I don't know

[^1]: publishes a `patch` release, for devDependencies use `internal`
[^2]: will not publish a new version

### Test Plan

1. On Safari
2. Make a new text shape and start typing
3. At a certain point the text starts to wrap without the width having
been set


### Release Notes

- Fix text wrapping differently on Safari and Chrome/Firefox

Before/After

<image width="350"
src="https://github.com/tldraw/tldraw/assets/98838967/320171b4-61e0-4a41-b8d3-830bd90bea65">
<image width="350"
src="https://github.com/tldraw/tldraw/assets/98838967/b42d7156-0ce9-4894-9692-9338dc931b79">

apps/examples/e2e/tests/test-text.spec.ts

@@ -7,7 +7,7 @@ export function sleep(ms: number) {
 }
 
 const measureTextOptions = {
-	width: 'fit-content',
+	width: null,
 	fontFamily: 'var(--tl-font-draw)',
 	fontSize: 24,
 	lineHeight: 1.35,