♻️ Some refactoring started within download.py.

✨ Track extension can be ignored while skipping files. Closes #11.
✨ Started to implement MPEG DASH download support.

tidal_dl_ng/helper/format.py

@@ -0,0 +1,18 @@
+def is_xml(value: str) -> bool:
+    result = False
+
+    if value:
+        if value.startswith("<?xml"):
+            result = True
+
+    return result
+
+
+def is_json(value: str) -> bool:
+    result = False
+
+    if value:
+        if value.startswith("{"):
+            result = True
+
+    return result