[ie/streaks] Fix extractor (#16413)

* Add `api_key` extractor-arg
* Fix SSAI detection
* Add hooks for custom Streaks playback API requests

Authored by: doe1080

README.md

@@ -1969,6 +1969,9 @@ The following extractors use this feature:
 #### sonylivseries
 * `sort_order`: Episode sort order for series extraction - one of `asc` (ascending, oldest first) or `desc` (descending, newest first). Default is `asc`
 
+#### streaks
+* `api_key`: API key for the `X-Streaks-Api-Key` header
+
 #### tver
 * `backend`: Backend API to use for extraction - one of `streaks` (default) or `brightcove` (deprecated)