agent: rust — add preferences webview injection for zero-flash hydration

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src-tauri/src/commands/windows.rs

@@ -1,5 +1,7 @@
 use tauri::{Emitter, Manager, WebviewUrl, WebviewWindowBuilder};
 
+use crate::PreferencesScript;
+
 /// Open a floating always-on-top task window.
 #[tauri::command]
 pub async fn open_task_window(
@@ -13,7 +15,7 @@ pub async fn open_task_window(
         return Ok(());
     }
 
-    WebviewWindowBuilder::new(
+    let mut builder = WebviewWindowBuilder::new(
         &app,
         "tasks-float",
         WebviewUrl::App("/float".into()),
@@ -23,9 +25,16 @@ pub async fn open_task_window(
     .min_inner_size(400.0, 400.0)
     .always_on_top(true)
     .decorations(false)
-    .resizable(true)
-    .build()
-    .map_err(|e| e.to_string())?;
+    .resizable(true);
+
+    // Inject preferences before Svelte mounts
+    if let Some(script) = app.try_state::<PreferencesScript>() {
+        if !script.0.is_empty() {
+            builder = builder.initialization_script(&script.0);
+        }
+    }
+
+    builder.build().map_err(|e| e.to_string())?;
 
     Ok(())
 }
@@ -41,7 +50,7 @@ pub async fn open_viewer_window(
         return Ok(());
     }
 
-    WebviewWindowBuilder::new(
+    let mut builder = WebviewWindowBuilder::new(
         &app,
         "transcript-viewer",
         WebviewUrl::App("/viewer".into()),
@@ -50,9 +59,16 @@ pub async fn open_viewer_window(
     .inner_size(600.0, 700.0)
     .min_inner_size(450.0, 500.0)
     .decorations(false)
-    .resizable(true)
-    .build()
-    .map_err(|e| e.to_string())?;
+    .resizable(true);
+
+    // Inject preferences before Svelte mounts
+    if let Some(script) = app.try_state::<PreferencesScript>() {
+        if !script.0.is_empty() {
+            builder = builder.initialization_script(&script.0);
+        }
+    }
+
+    builder.build().map_err(|e| e.to_string())?;
 
     Ok(())
 }