fix(expr-ir): Backport __replace__ typing for <3.13

[dangotbanned]

Description

Aiming to fix this noise:

./.venv/bin/uv run --no-sync pyright
/home/runner/work/narwhals/narwhals/narwhals/_plan/_nodes.py
  /home/runner/work/narwhals/narwhals/narwhals/_plan/_nodes.py:528:33 - error: Cannot access attribute "__replace__" for class "ExprIR"
    Attribute "__replace__" is unknown (reportAttributeAccessIssue)
  /home/runner/work/narwhals/narwhals/narwhals/_plan/_nodes.py:533:28 - error: Cannot access attribute "__replace__" for class "ExprIR"
    Attribute "__replace__" is unknown (reportAttributeAccessIssue)
  /home/runner/work/narwhals/narwhals/narwhals/_plan/_nodes.py:636:28 - error: Cannot access attribute "__replace__" for class "ExprIR"
    Attribute "__replace__" is unknown (reportAttributeAccessIssue)
  /home/runner/work/narwhals/narwhals/narwhals/_plan/_nodes.py:648:43 - error: Cannot access attribute "__replace__" for class "ExprIR"
    Attribute "__replace__" is unknown (reportAttributeAccessIssue)
  /home/runner/work/narwhals/narwhals/narwhals/_plan/_nodes.py:661:36 - error: Cannot access attribute "__replace__" for class "ExprIR"
    Attribute "__replace__" is unknown (reportAttributeAccessIssue)
  /home/runner/work/narwhals/narwhals/narwhals/_plan/_nodes.py:686:33 - error: Cannot access attribute "__replace__" for class "ExprIR"
    Attribute "__replace__" is unknown (reportAttributeAccessIssue)
/home/runner/work/narwhals/narwhals/narwhals/_plan/expressions/function_expr.py
  /home/runner/work/narwhals/narwhals/narwhals/_plan/expressions/function_expr.py:122:24 - error: Cannot access attribute "__replace__" for class "FunctionExpr[FunctionT_co@FunctionExpr]*"
    Attribute "__replace__" is unknown (reportAttributeAccessIssue)
/home/runner/work/narwhals/narwhals/narwhals/_plan/plans/conversion.py
  /home/runner/work/narwhals/narwhals/narwhals/_plan/plans/conversion.py:552:57 - error: Cannot access attribute "__replace__" for class "SortMultipleOptions"
    Attribute "__replace__" is unknown (reportAttributeAccessIssue)
8 errors, 0 warnings, 0 informations

Related issues

• Follow-up from fix(expr-ir): Add compat for old polars #3617
• Child of feat(RFC): A richer Expr IR #2572