[ios]add a note on plugin's init being deferred

[hellohuanlin]

Description of what this PR is changing or adding, and why:

Add a note on plugin's init method being deferred as well.

Issues fixed by this PR (if any):

NA

PRs or commits this PR depends on (if any):

NA

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[gemini-code-assist]

Code Review

This pull request updates the documentation for UISceneDelegate breaking changes to note that plugins' init methods are deferred until scene connection. The review feedback suggests formatting the added sentence to start on a new line to adhere to semantic line break guidelines.

[gemini-code-assist]

According to the style guide for Dart and Flutter websites, each sentence should start on a new line to adhere to semantic line breaks. Please move the new sentence starting with "Plugins'" to its own line.

Suggested change

	`scene:willConnectToSession:options:` callback. Plugins'
	`init` methods are also deferred until scene connection.
	`scene:willConnectToSession:options:` callback.
	Plugins' `init` methods are also deferred until scene connection.

[vashworth]

I don't think that's technically true. It's deferred to once the ViewController is added to the view hierarchy I believe, which happens before scene connection I thought

[hellohuanlin]

IIRC it's happening in awakeFromNib, which is when VC is loaded from the xib file, but not necessarily been added to the view hierarchy. I rephrased it a bit.

[flutter-website-bot]

Staged preview of the updated docs.flutter.dev site (updated for commit c09b049):

https://flutter-docs-prod--docs-pr13644-uiscene-note-on-plugin-emtcs8gy.web.app

[flutter-website-bot]

Staged preview of the updated flutter.dev site (updated for commit c09b049):

https://flutter-dev-230821--www-pr13644-uiscene-note-on-plugin-vcr679su.web.app

[parlough]

I don't understand a lot of this doc, but is the point of this addition that plugin registration methods are now also called too late to set up the relevant APIs?

If so, can we focus on that and drop the FlutterViewController mention? Something like:

Your plugin's registration method is also
called too late to configure these APIs in.