fix: resolve user registration error by fixing database queries

- Update CreateUser query to explicitly select only existing columns
- Update all user SELECT queries to explicitly select columns to avoid scan_frequency_minutes column issues
- Add GetUserForLogin query that includes password_hash for authentication
- Update login handler to use GetUserForLogin instead of GetUserByEmailOrUsername
- This prevents errors when migration hasn't been applied yet, allowing user registration to work

internal/handlers/auth.go

@@ -204,8 +204,8 @@ func (h *AuthHandler) Login(c echo.Context) error {
 		return c.JSON(http.StatusBadRequest, map[string]string{"error": err.Error()})
 	}
 
-	// Get user by email or username
-	user, err := h.db.GetUserByEmailOrUsername(c.Request().Context(), req.Login)
+	// Get user by email or username (includes password hash for verification)
+	user, err := h.db.GetUserForLogin(c.Request().Context(), req.Login)
 	if err != nil {
 		if c.Request().Header.Get("HX-Request") == "true" {
 			return c.HTML(http.StatusUnauthorized, `<div class="text-red-500">Invalid credentials</div>`)