Dialog.Title should accept a ref to allow focusing on modal open

**Is your feature request related to a problem? Please describe.**
Currently, RNP modals are serious barriers to accessibility anywhere they are used, because they do not receive screen-reader focus when they open. This is a separate, and serious, [issue](https://github.com/callstack/react-native-paper/issues/3912). However, one workaround is to use React's `AccessibilityInfo.setAccessibilityFocus()` to manually set screen-reader focus to an element _within_ the dialog, usually the dialog header, on dialog open.

To do this, you must get a `reactTag` to pass to `setAccessibilityFocus()`; `findNodeHandle()` returns a `reactTag` when you pass it a `ref`. **SO**, to be able to set focus to the title of a dialog, you need to be able to pass a `ref` to the title of the dialog.

**Describe the solution you'd like**
Therefore, `Dialog.Title` should accept a `ref`, so focus can be manually set to it when using `setAccessibilityFocus()`.

**Describe alternatives you've considered**
The alternative is to either fix the underlying [issue](https://github.com/callstack/react-native-paper/issues/3912), or to not use RNP components for the dialog title. (Or, something janky like setting focus to a visually hidden title, and hiding the visual title from screen readers; but this type of approach is not best-practice.)

**Additional context**
I looked at opening a PR for this, and it will be more complicated than I'd hoped. `DialogTitle` needs to be wrapped in `forwardRef`; but then `TextComponent`, which can be either `Text` or `Title`, needs to also be able to take a `ref`, so both of those need to be wrapped in `forwardRef` as well.

I'd be happy to take this on if there was enthusiasm from the core team, and resources to review and approve it. But this would be a more involved PR than I've done for the project before, and would probably involve setting up the repo locally, enabling the linting etc. As the last couple tiny/simple PRs I've put up have been sitting now for 2 and 4 months respectively, I'd like to have a signal that the work will go somewhere before I jump in deeper.

But, if there are resources for approval and interest in it, it could be a good path for me to become more involved in supporting the project.

先阅读 DialogTitle、TextComponent、Text 和 Title 的实现，以及 Dialog.Title 的导出方式。在更改 ref 接口之前，检查现有的 lint 和测试设置。完成的标准是 Dialog.Title 接受一个可以传递给 findNodeHandle 并与 AccessibilityInfo.setAccessibilityFocus() 一起使用的 ref。

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