feat(core): import_lastpass parser — happy-path Login

Pins the parse_lastpass_csv signature and ImportWarning shape.
A single LastPass row with name/url/username/password round-trips
to a Login item with a freshly-minted ID. Header validation
rejects shape mismatches with a clear message.

TOTP, grouping, fav, SecureNote rows, and error paths land in
Tasks 3-6.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

crates/relicario-core/tests/import_lastpass.rs

@@ -0,0 +1,46 @@
+//! LastPass CSV importer — parser coverage.
+
+use relicario_core::import_lastpass::{parse_lastpass_csv, ImportWarning};
+use relicario_core::ItemCore;
+
+const HEADER: &str = "url,username,password,totp,extra,name,grouping,fav";
+
+#[test]
+fn single_login_row_round_trips() {
+    let csv = format!(
+        "{HEADER}\n\
+         https://github.com/login,alice,hunter2,,,GitHub,,",
+    );
+    let (items, warnings) = parse_lastpass_csv(csv.as_bytes()).unwrap();
+    assert_eq!(items.len(), 1, "one item expected");
+    assert!(warnings.is_empty(), "no warnings expected");
+
+    let item = &items[0];
+    assert_eq!(item.title, "GitHub");
+    assert!(!item.favorite);
+    assert!(item.group.is_none());
+    match &item.core {
+        ItemCore::Login(l) => {
+            assert_eq!(l.username.as_deref(), Some("alice"));
+            assert_eq!(l.password.as_deref().map(String::as_str), Some("hunter2"));
+            assert_eq!(l.url.as_ref().map(|u| u.as_str()), Some("https://github.com/login"));
+            assert!(l.totp.is_none());
+        }
+        other => panic!("expected Login, got {:?}", other),
+    }
+}
+
+#[test]
+fn item_id_is_freshly_minted() {
+    // Decision D12: title collisions don't dedupe; each row gets a fresh ID.
+    let csv = format!("{HEADER}\nhttps://x,u,p,,,Same,,\nhttps://x,u,p,,,Same,,");
+    let (items, _) = parse_lastpass_csv(csv.as_bytes()).unwrap();
+    assert_eq!(items.len(), 2);
+    assert_ne!(items[0].id, items[1].id, "IDs must be unique even for identical names");
+}
+
+// Assertion helper used by later tests.
+#[allow(dead_code)]
+fn first_warning_message(warnings: &[ImportWarning]) -> String {
+    warnings.first().expect("expected at least one warning").message.clone()
+}