fix: validate Quick Connect and ~/.ssh/config imports; unknown enum values no longer reset a profile's config

- Quick Connect runs the same validation as saved profiles, so an SSH
  connection without a username fails up front with a clear message (F5).
- ~/.ssh/config imports fill a missing User (and jump-host user) with the
  local user name, as ssh does, and skip blocks that still don't validate,
  reporting how many (F6).
- An unrecognised hostKeyPolicy/lineEnding/parity/flowControl/direction in
  a stored config falls back to that field's default instead of failing
  the whole JSON column and silently resetting every other setting; parse
  failures that remain are logged (F7).

rust/app/src/app.rs

@@ -586,9 +586,13 @@ impl App {
                 Request::Connect(id) => self.connect_profile(&id, false),
                 Request::ConnectQuick(p) => {
                     let name = if p.display_name.is_empty() { p.host.clone() } else { p.display_name.clone() };
-                    let sid = self.s.svc.connect_quick(p);
-                    self.add_session(&sid, true);
-                    self.s.info(format!("Connecting to {name}…"));
+                    match self.s.svc.connect_quick(p) {
+                        Ok(sid) => {
+                            self.add_session(&sid, true);
+                            self.s.info(format!("Connecting to {name}…"));
+                        }
+                        Err(e) => self.s.error(format!("Can't connect to {name}: {e}")),
+                    }
                 }
                 Request::ReloadProfiles => self.s.reload_profiles(),
                 Request::ReloadPreferences => {

rust/app/src/chrome.rs

@@ -80,7 +80,7 @@ pub fn title_bar(app: &mut App, ui: &mut Ui) {
                 if item(ui, icon::FILE_ARROW_DOWN, "Import ~/.ssh/config", "") {
                     match app.s.svc.import_ssh_config(None, "SSH Config") {
                         Ok(n) => {
-                            app.s.success(format!("Imported {n} host(s) from ~/.ssh/config"));
+                            app.s.success(crate::settings::ssh_import_summary(n));
                             app.s.reload_profiles();
                         }
                         Err(e) => app.s.error(format!("Import failed: {e}")),

rust/app/src/quick_connect.rs

@@ -184,4 +184,21 @@ mod tests {
         let p = q.profile().unwrap();
         assert_eq!((p.port, p.username.as_str()), (0, ""));
     }
+
+    #[test]
+    fn quick_profiles_pass_validation_unless_incomplete() {
+        use nexus_core::validation::validate_profile;
+        for proto in PROTOCOLS {
+            let mut q = QuickConnect { host: "box".into(), username: "me".into(), ..Default::default() };
+            q.set_protocol(proto);
+            let mut p = q.profile().unwrap();
+            p.normalize();
+            assert!(validate_profile(&p).is_ok(), "{proto:?}: {:?}", validate_profile(&p).err().map(|e| e.to_string()));
+        }
+        let mut q = QuickConnect { host: "box".into(), ..Default::default() };
+        q.set_protocol(Protocol::Ssh);
+        let mut p = q.profile().unwrap();
+        p.normalize();
+        assert!(validate_profile(&p).is_err(), "SSH needs a username");
+    }
 }

rust/app/src/settings.rs

@@ -543,7 +543,7 @@ impl Settings {
             if widgets::button(ui, icon::DOWNLOAD_SIMPLE, "Import ~/.ssh/config").clicked() {
                 match s.svc.import_ssh_config(None, "SSH Config") {
                     Ok(n) => {
-                        s.success(format!("Imported {n} host(s) from ~/.ssh/config"));
+                        s.success(ssh_import_summary(n));
                         s.request(Request::ReloadProfiles);
                     }
                     Err(e) => s.error(format!("SSH config import failed: {e}")),
@@ -934,6 +934,12 @@ Open two or more sessions and press {Mod+Shift+B} to turn on broadcast mode. Eve
     ),
 ];
 
+pub fn ssh_import_summary((n, skipped): (usize, usize)) -> String {
+    match skipped {
+        0 => format!("Imported {n} host(s) from ~/.ssh/config"),
+        k => format!("Imported {n} host(s) from ~/.ssh/config; skipped {k} that couldn't be used as-is"),
+    }
+}
 #[cfg(test)]
 mod tests {
     use super::*;