…rovider` (tldraw#7053)

if you wanted to use TldrawEditor by itself, you weren't able to use
some tldraw shapes b/c they relied on `TldrawUiContextProvider` being
present which could bloat your bundle size unnecessarily if you didn't
need all that extra stuff

H/T to @derekcicerone for flagging this one — thanks!

### Change type

- [x] `bugfix`
- [ ] `improvement`
- [ ] `feature`
- [ ] `api`
- [ ] `other`

### Test plan

- [x] Unit tests
- [ ] End to end tests

### Release notes

- editor: be able to use TldrawEditor without needing
`TldrawUiContextProvider`

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Make note shape RTL logic resilient to missing UI translation context
so TldrawEditor works standalone, add CSS.supports polyfill, and expand
shape rendering tests.
> 
> - **Editor / Shapes**:
> - Update `NoteShapeUtil` to use optional `TranslationsContext`
(fallback to LTR) for RTL/tab navigation, avoiding hard dependency on
`TldrawUiContextProvider`.
> - **UI / Translations**:
> - Export `TranslationsContext` from
`ui/hooks/useTranslation/useTranslation` (marked internal).
> - **Tests**:
> - Revamp `TldrawEditor.test.tsx` to render and validate all core
shapes (no error boundaries), use `defaultShapeUtils`, and test
selection/tool switching with rich text helpers.
> - **Tooling / Polyfills**:
> - Add `CSS.supports` polyfill in `internal/config/vitest/setup.ts` for
color space-related tests.
> 
> <sup>Written by [Cursor
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<!-- /CURSOR_SUMMARY -->

…rovider (#8011)

In order to allow SDK users to use `TldrawSelectionForeground` with
`TldrawEditor` directly (without wrapping in `TldrawUiContextProvider`),
this PR makes `useTranslation()` gracefully fall back to default English
translations when `TranslationsContext` is not available.

Closes #6236

PR #7053 partially addressed this for `NoteShapeUtil` but missed
`TldrawSelectionForeground` and its child components
(`RotateCornerHandle`, `MobileRotateHandle`, `TldrawCropHandles`), which
all call `useTranslation()`. Rather than patching each component
individually, this fixes `useTranslation()` itself so all current and
future consumers are covered.

### Change type

- [x] `bugfix`

### Test plan

1. Use `TldrawEditor` with `components={{ SelectionForeground:
TldrawSelectionForeground }}` but without `TldrawUiContextProvider`
2. Create and select a shape
3. Verify the selection foreground renders correctly with resize/rotate
handles

- [x] Unit tests

### Release notes

- Fix `TldrawSelectionForeground` crashing when used without
`TldrawUiContextProvider`

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Low Risk**
> Small, localized change to a hook to avoid throwing when context is
missing, plus a targeted regression test; minimal behavioral impact
beyond preventing crashes.
> 
> **Overview**
> Fixes a crash when rendering `TldrawSelectionForeground` (and other UI
pieces calling `useTranslation`) without `TldrawUiContextProvider` by
making `useTranslation()` fall back to `DEFAULT_TRANSLATION` when
`TranslationsContext` is absent.
> 
> Adds a unit test that mounts `TldrawEditor` with `SelectionForeground:
TldrawSelectionForeground` and asserts selecting a shape renders the
selection foreground without triggering the error boundary.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
95d5ef8. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->