refactor: require an explicit database username

src/connection.rs

@@ -85,12 +85,11 @@ struct Form {
 
 impl Default for Form {
     fn default() -> Self {
-        let user = std::env::var("USER").unwrap_or_default();
         Self {
             provider: 0,
             focus: 0,
             tls: 0,
-            postgres: ["localhost", "5432", "postgres", &user, ""].map(Input::from),
+            postgres: ["localhost", "5432", "postgres", "", ""].map(Input::from),
             path: Input::default(),
             error: None,
         }

src/main.rs

@@ -40,6 +40,7 @@ Navigation:
   Tab/Shift-Tab changes fields; Left/Right changes TLS when that field is focused.
   Enter connects; Esc cancels; Ctrl-U clears a field. Pasting is supported.
   Form details are session-only. Passwords clear after connecting or cancelling.
+  Enter the database user explicitly; the operating-system username is not used.
 
 PostgreSQL reads are enforced read-only and have a 5-second query timeout.
 SQLite files are opened read-only, with a 5-second lock wait but no query timeout.