chore(release): v0.3.4

- Connection picker lists every database (system + non-ONLINE), not just online
  user DBs.
- Prominent highlighted UPDATES button in the topbar + guided download → quit →
  install → reopen flow (POST /api/shutdown so the MSI in-place upgrade isn't
  blocked). Update UI removed from Help.

Author: sqlopt

Cargo.lock

@@ -10,7 +10,7 @@ members = [
 ]
 
 [workspace.package]
-version = "0.3.3"
+version = "0.3.4"
 edition = "2021"
 license = "Apache-2.0"
 repository = "https://github.com/singhpratech/dbopt"