Fix pending message feedback (#3543)

## Summary

- Keep `Sending…` beside message timestamps, including grouped pending
messages.
- Match the profile-card hover surface to inactive channel rows.

## Snapshots

### Pending message

![Pending message
status](https://raw.githubusercontent.com/block/buzz/655189aec0904677a68651f8aabf0e17d69734cd/pr-3543--pending-message-inline.png)

### Profile hover

![Profile
hover](https://raw.githubusercontent.com/block/buzz/655189aec0904677a68651f8aabf0e17d69734cd/pr-3543--profile-hover.png)

## Validation

- `pnpm -C desktop typecheck`
- `pnpm -C desktop check:file-sizes`
- `pnpm -C desktop build:e2e`
- `pnpm -C desktop exec playwright test
tests/e2e/message-feedback-snapshots.spec.ts --project=smoke`

---------

Signed-off-by: kenny lopez <klopez4212@gmail.com>

desktop/src/shared/styles/globals/theme.css

@@ -481,6 +481,13 @@
   color: var(--buzz-muted-foreground);
 }
 
+/* Match the hover treatment used by inactive channel rows. */
+:root[data-buzz-sidebar]
+  [data-testid="app-sidebar"]
+  [data-testid="sidebar-profile-card"]:hover {
+  background-color: var(--buzz-hover-surface);
+}
+
 /*
  * App and settings sidebar section headings plus secondary footer text use the
  * same tint. Navigation rows keep their normal foreground in both sidebars.