feat: add ffmpeg to packages

packages/linux.txt

@@ -9,6 +9,7 @@ git
 jq
 unzip
 zip
+ffmpeg
 
 # Shell
 zsh

packages/windows.json

@@ -51,7 +51,8 @@
         { "PackageIdentifier": "WinSCP.WinSCP" },
         { "PackageIdentifier": "Streamlink.Streamlink" },
         { "PackageIdentifier": "ajeetdsouza.zoxide" },
-        { "PackageIdentifier": "Canonical.Ubuntu" }
+        { "PackageIdentifier": "Canonical.Ubuntu" },
+        { "PackageIdentifier": "Gyan.FFmpeg" }
       ],
       "SourceDetails": {
         "Argument": "https://cdn.winget.microsoft.com/cache",