restart hls session in some cases (#1880)

CHANGELOG.md

@@ -73,6 +73,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Improve trakt list URL validation; non-trakt URLs will no longer be requested
 - Prevent saving block templates when blocks are overlapping
   - This can happen if block durations are changed for blocks that are already on the template
+- Redirect variant playlist request to proper URL for starting `HLS Segmenter` session when no session is active
+  - This can happen when some clients "pause" for long enough for the session to stop in ETV
+  - When this happens, the client requests the temporary playlist URL e.g. `/iptv/session/1/hls.m3u8` (not the original URL `/iptv/channel/1.m3u8`)
+  - To fix, the client will be redirected back to the original URL in this case which will create a new session
 
 ## [0.8.7-beta] - 2024-06-26
 ### Added

ErsatzTV/Controllers/IptvController.cs

@@ -168,8 +168,8 @@ public class IptvController : ControllerBase
             return NotFound();
         }
 
-        _logger.LogWarning("Unable to locate session worker for channel {Channel}", channelNumber);
-        return NotFound();
+        _logger.LogWarning("Unable to locate session worker for channel {Channel}; will redirect to start session", channelNumber);
+        return RedirectToAction(nameof(GetHttpLiveStreamingVideo), new { channelNumber });
     }
 
     [HttpHead("iptv/channel/{channelNumber}.m3u8")]