Drop agent markers from code comments and the 0.2 prelude

PR-comment markers do not belong in source, and the 0.2 prelude text is
part of every composed 0.2 stage.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

crates/horizon-client-render/src/gfx/native_post.rs

@@ -1172,7 +1172,7 @@ pub fn frame_inputs(
             let k = super::native_shadow::distortion(s.distance, s.resolution);
             2.0 * s.distance / s.resolution.max(1) as f32 * (1.0 - k)
         }),
-        // 🤖 Agent: shader API 0.2's display fields, which 0.1 packs don't declare: SDR's values, also
+        // Shader API 0.2's display fields, which 0.1 packs don't declare: SDR's values, also
         // with HDR on, until HDR output is served for 0.2 packs.
         hdr: 0,
         headroom: 1.0,

crates/horizon-mods/src/index.rs

@@ -647,7 +647,7 @@ pub fn inspect(kind: &Kind, path: &Path) -> Result<Facts, String> {
                 ));
             }
             let m = pack.manifest;
-            // 🤖 Agent: players get only what the game draws without a switch, and a line that may
+            // Players get only what the game draws without a switch, and a line that may
             // still change in any release would break the packs listed for it.
             if m.api != horizon_shader_api::Api::V0_1 {
                 return Err(format!(

crates/horizon-shader-api/src/inputs.rs

@@ -362,7 +362,7 @@ mod tests {
         let wgsl = Frame::WGSL;
         assert_eq!(wgsl.fields.len(), 54);
         assert!(wgsl.fields.iter().all(|f| !f.doc.trim().is_empty()));
-        // 🤖 Agent: 0.1's 49 fields, then 0.2's five and the padding to a multiple of 16.
+        // 0.1's 49 fields, then 0.2's five and the padding to a multiple of 16.
         assert_eq!(
             std::mem::size_of::<Frame>(),
             6 * 64 + 15 * 16 + 8 * 16 + 2 * 16

crates/horizon-shader-api/src/reference.rs

@@ -108,7 +108,7 @@ pub fn markdown(api: Api) -> String {
         out += &table(kind.input(), None);
         if kind == StageKind::Material {
             let surface = table(&SURFACE, None);
-            // 🤖 Agent: 0.2's lit colour is linear light and may pass white; 0.1's reference keeps its text.
+            // 0.2's lit colour is linear light and may pass white; 0.1's reference keeps its text.
             out += &match api {
                 Api::V0_1 => surface,
                 Api::V0_2 => surface.replace(

crates/horizon-shader-api/src/stages.rs

@@ -132,7 +132,7 @@ const TONEMAP_RESOURCES: [Resource; 4] = [
 
 /// 0.2's colour boundary, in every 0.2 prelude: vanilla's 2.2 power both ways.
 const COLOR_HELPERS: &str = "\
-// 🤖 Agent: Negatives and NaN made 0 (a comparison with NaN is false), so no `pow` sees them.
+// Negatives and NaN made 0 (a comparison with NaN is false), so no `pow` sees them.
 fn horizon_sanitize(c: vec3<f32>) -> vec3<f32> {
     return select(vec3<f32>(0.0), c, c > vec3<f32>(0.0));
 }
@@ -142,7 +142,7 @@ fn horizon_decode(c: vec3<f32>) -> vec3<f32> {
 fn horizon_encode(c: vec3<f32>) -> vec3<f32> {
     return pow(horizon_sanitize(c), vec3<f32>(1.0 / 2.2));
 }
-// 🤖 Agent: Alpha is coverage: it stays as it is.
+// Alpha is coverage: it stays as it is.
 fn horizon_decode_rgba(c: vec4<f32>) -> vec4<f32> {
     return vec4<f32>(horizon_decode(c.rgb), c.a);
 }
@@ -781,7 +781,7 @@ impl StageKind {
             (Api::V0_2, StageKind::Vertex) => VERTEX_ENTRIES_0_2,
             (Api::V0_2, StageKind::Weather) => WEATHER_ENTRIES_0_2,
             (Api::V0_2, StageKind::Post) => POST_ENTRIES_0_2,
-            // 🤖 Agent: 0.1 has no tonemap stage: a manifest with one is refused before it is built.
+            // 0.1 has no tonemap stage: a manifest with one is refused before it is built.
             (_, StageKind::Tonemap) => TONEMAP_ENTRIES,
         }
     }

crates/horizon-shader-api/tests/reference.rs

@@ -137,7 +137,7 @@ fn the_frame_s_wgsl_layout_is_the_uploaded_struct_s() {
     let (wgsl, span) = frame_layout(Api::V0_2);
     assert_eq!(span, std::mem::size_of::<Frame>());
     assert_eq!(wgsl, rust);
-    // 🤖 Agent: 0.1 declares the start of the same buffer.
+    // 0.1 declares the start of the same buffer.
     let (wgsl, span) = frame_layout(Api::V0_1);
     assert_eq!(wgsl, rust[..Frame::FIELDS_0_1]);
     assert_eq!(span, rust[Frame::FIELDS_0_1].1);