feat: preliminary DASH support (for freetube/yattee, no manifest)

rewrites struct returned by innertube with video url retrieved by yt-dlp
works on freetube with proxying disabled; enabling proxying causes
horrible performance. yattee seems unaffected.

ythdd_extractor.py

@@ -82,7 +82,7 @@ stage3_headers = {
 	"Sec-Fetch-Mode": "navigate",
 	"Content-Type": "application/json",
 	"X-Youtube-Client-Name": "1",
-	"X-Youtube-Client-Version": "2.20251014.01.00",
+	"X-Youtube-Client-Version": "2.20251103.01.00",
 	"Origin": "https://www.youtube.com",
 	"Accept-Encoding": "gzip, deflate, br",
 	"Cookie": "PREF=hl=en&tz=UTC; SOCS=CAI"
@@ -94,7 +94,7 @@ stage3_body = {
 		"client":
 		{
 			"clientName": "WEB",
-			"clientVersion": "2.20251014.01.00",
+			"clientVersion": "2.20251103.01.00",
 			"hl": "en",
 			"timeZone": "UTC",
 			"utcOffsetMinutes": 0
@@ -114,7 +114,7 @@ web_context_dict = {
             'deviceModel': '',
             'userAgent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:144.0) Gecko/20100101 Firefox/144.0,gzip(gfe)',
             'clientName': 'WEB',
-            'clientVersion': '2.20251030.01.00',
+            'clientVersion': '2.20251103.01.00',
             'osName': 'Windows',
             'osVersion': '10.0',
             'screenPixelDensity': 2,