Localize rich-text message preview labels; split audio into voice/music

Thread PresentationStrings through RichText/InstantPageBlock/InstantPage
previewText(), replacing the hardcoded //TODO:localize placeholders
("Photo", "Fx", "Table", "Map", ...) with localized keys and reusing the
existing Message.Photo/Video/Location strings. Add RichTextPreview.Formula
("[formula]"), RichTextPreview.Table ("[table]"), and RichTextPreview.Music
("Music").

The .audio block previously rendered the wrong label (Message.Audio is
"Voice Message"). Thread InstantPage.media down so the block can resolve
media[id] as TelegramMediaFile and split: isVoice -> "Voice Message",
otherwise -> "Music", mirroring MessageContentKind's voice/music handling.

Update both previewText() call sites (MessageContentKind, ChatListItemStrings)
to pass strings, and complete the InstantPageListItem migration that was
left on the old signature.

Also remove the dead streaming-status ("Thinking...") rendering block from
ChatMessageTextBubbleContentNode (guarded by an always-false `!"".isEmpty`)
along with the now-orphaned streamingTextFrame layout machinery it fed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

submodules/TelegramStringFormatting/Sources/MessageContentKind.swift

@@ -314,7 +314,7 @@ public func messageContentKind(contentSettings: ContentSettings, message: Engine
     }
     for attribute in message.attributes {
         if let attribute = attribute as? RichTextMessageAttribute {
-            return .text(NSAttributedString(string: attribute.instantPage.previewText()))
+            return .text(NSAttributedString(string: attribute.instantPage.previewText(strings: strings)))
         }
     }
     return .text(messageTextWithAttributes(message: message))