Centralize world and viewport game loops

Cargo.lock

@@ -4605,6 +4605,14 @@ dependencies = [
  "tokio",
 ]
 
+[[package]]
+name = "metacrate-game-loop"
+version = "0.0.1"
+dependencies = [
+ "metacrate-grid-world",
+ "metacrate-rendering-wgpu",
+]
+
 [[package]]
 name = "metacrate-grid-agent"
 version = "0.0.1"
@@ -4620,6 +4628,7 @@ dependencies = [
  "libremetaverse-rendering-simple",
  "libremetaverse-types",
  "mentra",
+ "metacrate-game-loop",
  "metacrate-lsl-tools",
  "metacrate-rendering-wgpu",
  "rustls",
@@ -4633,6 +4642,14 @@ dependencies = [
  "url",
 ]
 
+[[package]]
+name = "metacrate-grid-world"
+version = "0.0.1"
+dependencies = [
+ "libremetaverse",
+ "libremetaverse-types",
+]
+
 [[package]]
 name = "metacrate-lsl-tools"
 version = "0.0.1"