fix(Dialog): do not require ref forwarding

[layershifter]

Previous Behavior

<Dialog>
  {/* ❌ throws if `CustomComponent` does not forward a ref */}
  <CustomComponent />
</Dialog>

New Behavior

<Dialog>
  {/* ✅ does not throw */}
  <CustomComponent />
</Dialog>

A ref will be passed down via context to DialogSurface rendered by CustomComponent.

Related Issue(s)

Fixes #31808

[fabricteam]

📊 Bundle size report

Package & Exports	Baseline (minified/GZIP)	PR	Change
react-components react-components: entire library	1.095 MB 270.359 kB	1.095 MB 270.407 kB	148 B 48 B
react-dialog Dialog (including children components)	99.413 kB 29.881 kB	99.54 kB 29.905 kB	127 B 24 B

Unchanged fixtures

Package & Exports	Size (minified/GZIP)
react-components react-components: Button, FluentProvider & webLightTheme	69.141 kB 20.157 kB
react-components react-components: Accordion, Button, FluentProvider, Image, Menu, Popover	217.412 kB 63.063 kB
react-components react-components: FluentProvider & webLightTheme	44.442 kB 14.607 kB
react-portal-compat PortalCompatProvider	8.39 kB 2.64 kB
react-timepicker-compat TimePicker	106.751 kB 35.596 kB

_{🤖 This report was generated against 804c367079e2e7e5b3b0174eea96f034835dde4d}

[fabricteam]

Perf Analysis (@fluentui/react-components)

No significant results to display.

All results

Scenario	Render type	Master Ticks	PR Ticks	Iterations	Status
Avatar	mount	661	626	5000
Button	mount	321	325	5000
Field	mount	1186	1156	5000
FluentProvider	mount	738	702	5000
FluentProviderWithTheme	mount	82	84	10
FluentProviderWithTheme	virtual-rerender	40	36	10
FluentProviderWithTheme	virtual-rerender-with-unmount	73	78	10
MakeStyles	mount	904	885	50000
Persona	mount	1791	1765	5000
SpinButton	mount	1404	1412	5000
SwatchPicker	mount	1718	1705	5000