Use more generic error messages in gpui (#33651)

Follow-up of https://github.com/zed-industries/zed/pull/32537

Release Notes:

- N/A

crates/gpui/src/platform.rs

@@ -151,7 +151,7 @@ pub fn guess_compositor() -> &'static str {
 pub(crate) fn current_platform(_headless: bool) -> Rc<dyn Platform> {
     Rc::new(
         WindowsPlatform::new()
-            .inspect_err(|err| show_error("Error: Zed failed to launch", err.to_string()))
+            .inspect_err(|err| show_error("Failed to launch", err.to_string()))
             .unwrap(),
     )
 }

crates/gpui/src/platform/windows/window.rs

@@ -1299,12 +1299,8 @@ mod windows_renderer {
             size: Default::default(),
             transparent,
         };
-        BladeRenderer::new(context, &raw, config).inspect_err(|err| {
-            show_error(
-                "Error: Zed failed to initialize BladeRenderer",
-                err.to_string(),
-            )
-        })
+        BladeRenderer::new(context, &raw, config)
+            .inspect_err(|err| show_error("Failed to initialize BladeRenderer", err.to_string()))
     }
 
     struct RawWindow {