Fix timestamp queries for DLSS

[JMS55]

Timestamp queries have never worked for DLSS because I setup them up wrong when I initially wrote the code. This fixes it (and adds DLSS-RR time to the Solari example).

Basically we need to put the timestamp start on the command buffer before DLSS, and then the timestamp end on the command buffer right after DLSS.

Debug groups had to be removed because I can't use them across different command encoders.

[ChristopherBiscardi]

Timestamps seem high? or am I reading this wrong?

also a bit harder to find the dlss-rr in nsight, but doable.

render doc is also crashing for me on a dlss-related issue afaict

[JMS55]

Are you on a 4k monitor? Those numbers are not surprising for a 2080 TI. There's a table here: https://github.com/NVIDIA/DLSS/blob/main/doc/DLSS-RR%20Integration%20Guide.pdf (page 9).

Generally Solari's recommended minimum is going to be an RTX 4070 (especially once wgpu gets support for SER and OMM).

Renderdoc crash is interesting. Renderdoc doesn't support the DLSS extensions needed, but we also shouldn't be crashing. It's an unrelated bug to this PR though.

[ChristopherBiscardi]

Are you on a 4k monitor

1080p high-refresh rate (can go up to 240-ish).

If the numbers are expected for my hardware (which is out of the support bracket) then this is working afaict.