feat: add hostname sanitization function and integrate it into user step processing

src/steps/users.rs

@@ -77,6 +77,24 @@ fn is_valid_hostname(s: &str) -> bool {
     s.chars().all(|c| c.is_ascii_alphanumeric() || c == '-')
 }
 
+/// Otomatik hostname üretirken nokta, boşluk ve geçersiz karakterleri kaldırır.
+fn sanitize_hostname(s: &str) -> String {
+    let mut hostname: String = s
+        .chars()
+        .filter(|c| c.is_ascii_alphanumeric())
+        .collect();
+
+    if hostname.len() > 63 {
+        hostname.truncate(63);
+    }
+
+    if hostname.is_empty() {
+        "host".to_string()
+    } else {
+        hostname
+    }
+}
+
 fn password_strength(p: &str) -> (String, egui::Color32) {
     let len = p.len();
     let has_upper = p.chars().any(|c| c.is_uppercase());
@@ -112,13 +130,14 @@ impl InstallerStep for UsersStep {
                 .unwrap_or_default()
                 .trim()
                 .to_string();
+            let sys_hostname = sanitize_hostname(&sys_hostname);
             if !sys_hostname.is_empty() && sys_hostname != "localhost" {
                 state.hostname = sys_hostname;
             }
         }
         // Hâlâ boşsa ve username varsa username-pc öner
         if state.hostname.is_empty() && !state.username.is_empty() {
-            state.hostname = format!("{}-pc", state.username);
+            state.hostname = sanitize_hostname(&format!("{}pc", state.username));
         }
     }