VP9-improvements (#132)

- Improves MMNV request handling by tracking active clock requests per session and returning the effective requested rate for each module.
- Treats sentinel clock requests (`0` / negative values) as request clears.
- Preserves VP9 segment maps across inter frames, resetting them for key/intra/size-change cases.
- Avoids stale VP9 motion-vector state by disabling previous MV lookup on key frames and clearing output MVs for intra-only frames.

This fixes VP9 playback corruption seen in several Just Dance videos where stale segmentation/MV state could leak across frames and produce blocky/discolored output until a later refresh frame.
The MMNV changes also make the service behavior closer to what games expect when requesting and clearing NvDec clocks, removing the stub spam for this service.

Co-authored-by: MrKev312 <34964788+MrKev312@users.noreply.github.com>
Reviewed-on: https://git.ryujinx.app/projects/Ryubing/pulls/132
Reviewed-by: sh0inx <sh0inx@noreply.git.ryujinx.app>

src/Ryujinx.Horizon/Sdk/MmNv/Session.cs

@@ -5,22 +5,32 @@ namespace Ryujinx.Horizon.Sdk.MmNv
         public Module Module { get; }
         public uint Id { get; }
         public bool IsAutoClearEvent { get; }
-        public uint ClockRateMin { get; private set; }
-        public int ClockRateMax { get; private set; }
+        public uint RequestedClockRate { get; private set; }
+        public uint LastTimeout { get; private set; }
+        public bool HasActiveRequest { get; private set; }
 
         public Session(uint id, Module module, bool isAutoClearEvent)
         {
             Module = module;
             Id = id;
             IsAutoClearEvent = isAutoClearEvent;
-            ClockRateMin = 0;
-            ClockRateMax = -1;
+            RequestedClockRate = 0;
+            LastTimeout = uint.MaxValue;
+            HasActiveRequest = false;
         }
 
-        public void SetAndWait(uint clockRateMin, int clockRateMax)
+        public void SetAndWait(uint clockRate, uint timeout)
         {
-            ClockRateMin = clockRateMin;
-            ClockRateMax = clockRateMax;
+            RequestedClockRate = clockRate;
+            LastTimeout = timeout;
+            HasActiveRequest = true;
+        }
+
+        public void ClearRequest(uint timeout)
+        {
+            RequestedClockRate = 0;
+            LastTimeout = timeout;
+            HasActiveRequest = false;
         }
     }
 }