thread view: Fix some design papercuts (#36893)

Release Notes:

- N/A

---------

Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>
Co-authored-by: Ben Brandt <benjamin.j.brandt@gmail.com>
Co-authored-by: Matt Miller <mattrx@gmail.com>

crates/assistant_tools/src/find_path_tool.rs

@@ -435,8 +435,8 @@ mod test {
         assert_eq!(
             matches,
             &[
-                PathBuf::from("root/apple/banana/carrot"),
-                PathBuf::from("root/apple/bandana/carbonara")
+                PathBuf::from(path!("root/apple/banana/carrot")),
+                PathBuf::from(path!("root/apple/bandana/carbonara"))
             ]
         );
 
@@ -447,8 +447,8 @@ mod test {
         assert_eq!(
             matches,
             &[
-                PathBuf::from("root/apple/banana/carrot"),
-                PathBuf::from("root/apple/bandana/carbonara")
+                PathBuf::from(path!("root/apple/banana/carrot")),
+                PathBuf::from(path!("root/apple/bandana/carbonara"))
             ]
         );
     }

crates/assistant_tools/src/read_file_tool.rs

@@ -68,7 +68,7 @@ impl Tool for ReadFileTool {
     }
 
     fn icon(&self) -> IconName {
-        IconName::ToolRead
+        IconName::ToolSearch
     }
 
     fn input_schema(&self, format: LanguageModelToolSchemaFormat) -> Result<serde_json::Value> {