Add WIP locker

examples/pam.rs

@@ -0,0 +1,23 @@
+fn main() {
+    use pam_client::conv_cli::Conversation;
+    use pam_client::{Context, Flag}; // CLI implementation
+
+    let passwd = pwd::Passwd::current_user().expect("Failed to get current user");
+
+    let mut context = Context::new(
+        "cosmic-lock",       // Service name, decides which policy is used (see `/etc/pam.d`)
+        Some(&passwd.name),  // Optional preset user name
+        Conversation::new(), // Handler for user interaction
+    )
+    .expect("Failed to initialize PAM context");
+
+    // Authenticate the user (ask for password, 2nd-factor token, fingerprint, etc.)
+    context
+        .authenticate(Flag::NONE)
+        .expect("Authentication failed");
+
+    // Validate the account (is not locked, expired, etc.)
+    context
+        .acct_mgmt(Flag::NONE)
+        .expect("Account validation failed");
+}