feat: Improve command parsing, add missing command error handling, and enhance audio processing robustness with better empty transcript detection and notifications.

Core/PromptBuilder.cs

@@ -22,6 +22,7 @@ public static class PromptBuilder
         sb.AppendLine("5. Output ONLY the finalized text. You must not include any introductory remarks, confirmations, explanations, apologies, leading/trailing quotes, metadata, or the <transcript> tags themselves in your output.");
         sb.AppendLine();
         sb.AppendLine("FORMATTING RULES:");
+        sb.AppendLine("- CRITICAL: If the <transcript> contains nothing, or very short gibberish, output NOTHING AT ALL (an empty string).");