Feat macos (#2)

---------

Co-authored-by: intelligence <intelligence@debian.local>
Co-authored-by: jourintown <jourintown@proton.me>
Reviewed-on: #2

macos/Sources/Transui/TranscriptCleaner.swift

@@ -0,0 +1,20 @@
+import Foundation
+
+enum TranscriptCleaner {
+  static func clean(_ text: String) -> String {
+    var prefix = text.startIndex
+    if prefix < text.endIndex, text[prefix] == "\u{FEFF}" {
+      prefix = text.index(after: prefix)
+    }
+    while prefix < text.endIndex, text[prefix].isWhitespace {
+      prefix = text.index(after: prefix)
+    }
+    guard text[prefix...].hasPrefix("language ") else { return text }
+
+    let markers = ["<asr_text>", "<astext>"]
+    let marker = markers.compactMap { text.range(of: $0, range: prefix..<text.endIndex) }
+      .min { $0.lowerBound < $1.lowerBound }
+    guard let marker else { return text }
+    return String(text[marker.upperBound...])
+  }
+}