feat: Add YouTube video downloading capability with ytdl-core

- Add ytdl-core@4.11.5 dependency to CLI package
- Create YoutubeDownloader utility class with full functionality:
  * Video info extraction (title, duration, author, views)
  * URL validation for YouTube links
  * Video downloading with quality options
  * Audio-only downloading
  * Available formats listing
- Support for different quality settings and output formats
- Ready for use in n8n workflows and Railway deployment

Features:
✅ Download YouTube videos in various qualities
✅ Extract audio-only from videos
✅ Get comprehensive video metadata
✅ Validate YouTube URLs
✅ Custom output paths and filenames
✅ Error handling and validation

pnpm-lock.yaml

@@ -1732,6 +1732,9 @@ importers:
       yargs-parser:
         specifier: 21.1.1
         version: 21.1.1
+      ytdl-core:
+        specifier: ^4.11.5
+        version: 4.11.5
       zod:
         specifier: 'catalog:'
         version: 3.25.67
@@ -12532,6 +12535,10 @@ packages:
     resolution: {integrity: sha512-h5bgJWpxJNswbU7qCrV0tIKQCaS3blPDrqKWx+QxzuzL1zGUzij9XCWLrSLsJPu5t+eWA/ycetzYAO5IOMcWAQ==}
     hasBin: true
 
+  m3u8stream@0.8.6:
+    resolution: {integrity: sha512-LZj8kIVf9KCphiHmH7sbFQTVe4tOemb202fWwvJwR9W5ENW/1hxJN6ksAWGhQgSBSa3jyWhnjKU1Fw1GaOdbyA==}
+    engines: {node: '>=12'}
+
   madge@8.0.0:
     resolution: {integrity: sha512-9sSsi3TBPhmkTCIpVQF0SPiChj1L7Rq9kU2KDG1o6v2XH9cCw086MopjVCD+vuoL5v8S77DTbVopTO8OUiQpIw==}
     engines: {node: '>=18'}
@@ -12727,6 +12734,10 @@ packages:
   minifaker@1.34.1:
     resolution: {integrity: sha512-O9+c6GaUETgtKe65bJkpDTJxGcAALiUPqJtDv97dT3o0uP2HmyUVEguEGm6PLKuoSzZUmHqSTZ4cS7m8xKFEAg==}
 
+  miniget@4.2.3:
+    resolution: {integrity: sha512-SjbDPDICJ1zT+ZvQwK0hUcRY4wxlhhNpHL9nJOB2MEAXRGagTljsO8MEDzQMTFf0Q8g4QNi8P9lEm/g7e+qgzA==}
+    engines: {node: '>=12'}
+
   minimalistic-assert@1.0.1:
     resolution: {integrity: sha512-UtJcAD4yEaGtjPezWuO9wC4nwUnVH/8/Im3yEHQP4b67cXlD/Qr9hdITCU1xDbSEXg2XKNaP8jsReV7vQd00/A==}
 
@@ -16829,6 +16840,10 @@ packages:
     resolution: {integrity: sha512-GQHQqAopRhwU8Kt1DDM8NjibDXHC8eoh1erhGAJPEyveY9qqVeXvVikNKrDz69sHowPMorbPUrH/mx8c50eiBQ==}
     engines: {node: '>=18'}
 
+  ytdl-core@4.11.5:
+    resolution: {integrity: sha512-27LwsW4n4nyNviRCO1hmr8Wr5J1wLLMawHCQvH8Fk0hiRqrxuIu028WzbJetiYH28K8XDbeinYW4/wcHQD1EXA==}
+    engines: {node: '>=12'}
+
   yup@0.32.11:
     resolution: {integrity: sha512-Z2Fe1bn+eLstG8DRR6FTavGD+MeAwyfmouhHsIUgaADz8jvFKbO/fXc2trJKZg+5EBjh4gGm3iU/t3onKlXHIg==}
     engines: {node: '>=10'}
@@ -28619,6 +28634,11 @@ snapshots:
 
   lz-string@1.5.0: {}
 
+  m3u8stream@0.8.6:
+    dependencies:
+      miniget: 4.2.3
+      sax: 1.2.4
+
   madge@8.0.0(typescript@5.9.2):
     dependencies:
       chalk: 4.1.2
@@ -28830,6 +28850,8 @@ snapshots:
       nanoid: 3.3.11
       uuid: 8.3.2
 
+  miniget@4.2.3: {}
+
   minimalistic-assert@1.0.1: {}
 
   minimalistic-crypto-utils@1.0.1: {}
@@ -33841,6 +33863,12 @@ snapshots:
 
   yoctocolors@2.1.1: {}
 
+  ytdl-core@4.11.5:
+    dependencies:
+      m3u8stream: 0.8.6
+      miniget: 4.2.3
+      sax: 1.2.4
+
   yup@0.32.11:
     dependencies:
       '@babel/runtime': 7.26.10