Change NoScope opacity for spectators and replays

[timiimit]

Issue

NoScope mod was previously unwatchable in replays/spectator because cursor can be hidden for extended period of time which makes gameplay uninteresting.

Solution

This was addressed by making the smallest possible opacity in replays 50% by default. Additionally a SliderBar was added to Visual Settings in replays which can be used to control this value. SliderBar is visible only when watching a replay with NoScope mod.

Details

• In gameplay there is no difference
• In replays cursor opacity is now interpolated in interval [SliderBar chosen value, 1] instead of [0, 1] as was done previously
• While spectating a player cursor will be 50% transparent as minimum with no option to configure because Visual Settings are not shown.

[Joehuu]

Visual settings is the wrong place to do this (once you add more mod/replay-specific settings, it'll be a mess). There's already #19925 which spans on more than just one mod. Though, that PR just toggles mods on and off (or partially, see flashlight impl).

Not sure how useful is opacity or any other future mod display setting during a replay, but if it's wanted, it may be a popover when you right-click(?) a mod in replay.

Closing as incorrect direction.

[peppy]

Definitely should be part of the toggle support if at all.

[timiimit]

Toggling mods should be enough.