feat: add password management, reading persistence on feed switch, and spin animation

internal/db/db_test.go

@@ -102,4 +102,17 @@ func TestDatabaseOperations(t *testing.T) {
 	if stats.TotalFeeds != 1 || stats.TotalUnread != 1 || stats.TotalStarred != 1 || stats.TotalCategories != 1 {
 		t.Errorf("unexpected stats: %+v", stats)
 	}
+
+	// 8. Test UpdateUserPassword
+	newHash := "$2a$10$updatedhashvalue"
+	if err := database.UpdateUserPassword(u.ID, newHash); err != nil {
+		t.Fatalf("UpdateUserPassword failed: %v", err)
+	}
+	updatedUser, err := database.GetUserByUsername("admin")
+	if err != nil {
+		t.Fatalf("GetUserByUsername failed: %v", err)
+	}
+	if updatedUser.PasswordHash != newHash {
+		t.Errorf("expected hash %s, got %s", newHash, updatedUser.PasswordHash)
+	}
 }