Support for per-file content exclusion in Rename Suggestions

[olegtk]

To support intelligent Copilot content exclusion we need to associate each piece of context we provide to Rename suggestions with file path this context is coming from.

Switch to the new Editor API (RenameContext has file path property):

Task<IReadOnlyList<string>> GetSuggestionsAsync(ImmutableArray<RenameContext> context, CancellationToken cancellationToken);

from (this one has no file path):

Task<IReadOnlyList<string>> GetSuggestionsAsync(ImmutableDictionary<string, string[]> context, CancellationToken cancellationToken);

[AmadeusW]

LGTM. Thank you, Oleg!

[Cosifne]

Could you try to use the latest main and build this branch, and verify rename experience are working? (With Smart Rename on/off)
Asking this because we used to break the rename function because Lightup helper in public preview. So it would be worthy to make validate the modify light up helper part works before merge

[Cosifne]

Note: Should only merge once we validate the change works in VS main

[olegtk]

Validated on latest main, with and without smart rename, automatic and non-automatic, in various C# files and various symbol types, looks good.