fix(web): silence spurious console errors (meta + AudioContext)

Two independent sources of noise in the web console, both from the
default plugin set:

1. 'Failed to deserialize meta for asset shaders/*.wgsl'
   DefaultPlugins adds AssetPlugin with meta_check = Always, so bevy
   fetches <path>.meta for every shader. The shaders ship raw (no .meta
   files); on the trunk dev server those requests don't return a clean
   404 that bevy maps to NotFound, so bevy receives bytes and tries to
   RON-deserialize them as AssetMetaMinimal, logging a SpannedError per
   shader. Set meta_check = Never: it skips the meta lookup and uses the
   loader's default meta — correct for processor-free raw assets.

2. 'AudioContext was not allowed to start'
   The default AudioPlugin opens a WebAudio sink at startup; browsers
   block that until a user gesture and log it as a JS error. This app
   has no audio, so disable AudioPlugin entirely — removes the noise and
   shrinks the wasm binary.

src/main.rs

@@ -21,15 +21,35 @@ fn main() {
     }
 
     App::new()
-        .add_plugins(DefaultPlugins.set(WindowPlugin {
-            primary_window: Some(Window {
-                title: "singularity-rs".into(),
-                // On web, make the canvas track the browser window size.
-                fit_canvas_to_parent: true,
-                ..default()
-            }),
-            ..default()
-        }))
+        .add_plugins(
+            DefaultPlugins
+                .set(WindowPlugin {
+                    primary_window: Some(Window {
+                        title: "singularity-rs".into(),
+                        // On web, make the canvas track the browser window size.
+                        fit_canvas_to_parent: true,
+                        ..default()
+                    }),
+                    ..default()
+                })
+                // The shaders ship as raw `.wgsl` files with no companion
+                // `.meta` files. The default `AssetMetaCheck::Always` makes bevy
+                // fetch `<path>.meta` for every asset; on the web dev server
+                // those requests don't return a clean 404, so bevy receives
+                // bytes it tries to RON-deserialize as `AssetMetaMinimal` and
+                // logs a deserialization error per shader. `Never` skips the
+                // meta lookup entirely and uses the loader's default meta —
+                // exactly right for processor-free assets.
+                .set(AssetPlugin {
+                    meta_check: bevy::asset::AssetMetaCheck::Never,
+                    ..default()
+                })
+                // The app has no audio. The default AudioPlugin opens a WebAudio
+                // sink at startup, which browsers block until a user gesture and
+                // log as a noisy "AudioContext was not allowed to start" error.
+                // Dropping it removes that noise and shrinks the wasm binary.
+                .disable::<bevy::audio::AudioPlugin>(),
+        )
         .add_plugins(render::BlackHolePlugin)
         .run();
 }