feat: Replace ffmpeg with pw-record for audio capture and add service stop/disable to the install script.

Audio/AudioRecorder.cs

@@ -19,12 +19,12 @@ public static class AudioRecorder
             File.Delete(WavPath);
         }
 
-        Logger.LogDebug("Starting ffmpeg to record audio...");
+        Logger.LogDebug("Starting pw-record to record audio...");
 
         var pInfo = new ProcessStartInfo
         {
-            FileName = "ffmpeg",
-            Arguments = $"-f alsa -i default -y {WavPath}",
+            FileName = "pw-record",
+            Arguments = $"--rate=16000 --channels=1 --format=s16 \"{WavPath}\"",
             UseShellExecute = false,
             CreateNoWindow = true,
             RedirectStandardOutput = true,
@@ -50,17 +50,22 @@ public static class AudioRecorder
                 var process = Process.GetProcessById(pid.Value);
                 if (!process.HasExited)
                 {
-                    // Send gracefully? Process.Kill on linux sends SIGKILL by default.
-                    // But ffmpeg can sometimes handle SIGINT or SIGTERM if we use alternative tools or Process.Kill.
-                    // Standard .NET Process.Kill(true) kills the tree. Let's start with basic Kill.
-                    process.Kill();
-                    process.WaitForExit();
+                    // Gracefully stop pw-record using SIGINT to ensure WAV headers are finalizing cleanly
+                    Process.Start(new ProcessStartInfo
+                    {
+                        FileName = "kill",
+                        Arguments = $"-INT {pid.Value}",
+                        CreateNoWindow = true,
+                        UseShellExecute = false
+                    })?.WaitForExit();
+                    
+                    process.WaitForExit(2000); // give it a moment to flush
                 }
             }
             catch (Exception ex)
             {
                 // Process might already be dead
-                Console.WriteLine($"[AudioRecorder] Error stopping ffmpeg: {ex.Message}");
+                Console.WriteLine($"[AudioRecorder] Error stopping pw-record: {ex.Message}");
             }
             finally
             {