* fix: lp-polars api

* chore: remove small val filtering

* chore: remove redundant comment

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Co-authored-by: Fabian Hofmann <[email protected]>

* Replace pandas-based LP file writing with polars implementation

- Remove pandas-based LP writing functions and replace with polars versions
- Rename polars functions to remove '_polars' suffix for consistent API
- Create separate get_printers_scalar() for non-LP functions (highspy, gurobi, mosek)
- Update get_printers() to handle polars dataframes for LP writing
- Consolidate "lp" and "lp-polars" io_api options to use same implementation
- Remove unused imports and cleanup handle_batch function

* fix: restore NaN validation in polars-based variable bounds checking

The polars migration broke NaN validation because check_has_nulls_polars
only checked for null values, not NaN values. In polars, these are distinct
concepts. This fix enhances the validation to detect both null and NaN values
in numeric columns while avoiding type errors on non-numeric columns.

Fixes failing tests in test_inconsistency_checks.py that expected ValueError
to be raised when variables have NaN bounds.

…rovement, remove writing of redundant solution files (#497)

* perf: use xpress c interface and order of operations improvement

* perf: only write solution file if requested or needed

* refactor: adds no_solution_file_solvers constant

* Fix windows permission error when dumping model file

* Properly use file context when dumping model

* doc: add jupyter notebook with oetc example use

* doc: configure nbsphinx execution settings

Enable auto-execution with inline backend configuration
Exclude OETC notebook from automatic execution

* doc: update styles and address warnings

* refac: jupyter notebook format

… function when writing lp (#507)

* Fetch and display OETC worker error logs

* Fix pre-commit dependencies version mismatch

* fix: explicitly set outer join for expression merge

Set join="outer" when merging expressions without common coordinate
structure to ensure consistent behavior across xarray versions and
properly handle expressions with disjoint coordinates.

* doc: add release note for outer join fix in expression merge

* feat: add polars series for constant input

* add another test

* update doc

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Co-authored-by: Fabian Hofmann <[email protected]>

* Handle ImportError in xpress import

Also catch ImportError for xpress import. This should resolve rarely occuring compat problem with numpy packages

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Co-authored-by: Fabian Hofmann <[email protected]>