Tracs validation added. A warning is thrown if the input contains a video strem, but the requested output format doesn't support it

web/backend/api/formats.py

@@ -0,0 +1,25 @@
+"""Endpoint to expose format information to the frontend."""
+
+from fastapi import APIRouter
+
+from backend.constants import FORMAT_INFO
+
+router = APIRouter(prefix="/api", tags=["formats"])
+
+
+@router.get("/formats")
+async def get_formats():
+    """
+    Return the list of supported container formats with their properties.
+    """
+    return {
+        "formats": [
+            {
+                "name": name,
+                "ffmpeg": info["ffmpeg"],
+                "extension": info["ext"],
+                "audio_only": info["audio_only"],
+            }
+            for name, info in FORMAT_INFO.items()
+        ]
+    }