more flexible support to window (SimpleOps)

Here *SimpleOps* refer to one of:

- SimpleProject(TableSource)
- SimpleProject(Last Join)
- SImpleProject (Rename)
- SImpleProject (A last join ( SimpleProject (B last join C))
- ...

Known limits
- window op (the partition by & order by) may only refer to left most physical table inside simple project

There are already issues which actually part of this feature:
- https://github.com/4paradigm/OpenMLDB/issues/2563
- window union #2832

The issue describes extending window function support in SimpleOps. Start by reading the linked issue #2563 and PR #2832 to understand the current limitations. Examine the code for window operations and SimpleProject handling, likely in the query planner or optimizer. Determine how partition by and order by clauses are currently resolved and where they are restricted to the leftmost physical table.

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