refactor: change asset topology setup

[LeonHilf]

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• PR Title follows conventional commit messages
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)
• All commits in this PR are DCO signed-off (see CONTRIBUTING.md)

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Fixes #

What is the new behavior (if this is a feature change)?

Does this PR introduce a breaking change?

• Yes
• No

[Copilot]

Pull request overview

This PR refactors the asset-topology data model usage across the repo to align with the newer “lean topology” representation: Topology now stores station records in raw_stations plus canonical assets/asset_bays, and reconstructs MaterializedStation views via Topology.materialize_stations().

Changes:

• Updated action-set compression/expansion and many solver/importer call sites to operate on raw_stations + materialize_stations() rather than embedded station assets.
• Updated import/export pipelines (pandapower + powsybl/network-graph) to build topologies using RawStation and canonicalized assets/asset bays.
• Refreshed a large portion of tests and fixtures/data files to match the new topology structure.

Reviewed changes

Copilot reviewed 56 out of 56 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
packages/interfaces_pkg/tests/test_stored_action_set.py	Updates stored-action-set tests for RawStation/MaterializedStation usage.
packages/interfaces_pkg/tests/test_stored_action_set_performance.py	Updates performance test generator to build topologies from raw_stations and canonical assets.
packages/interfaces_pkg/tests/test_asset_topology.py	Adjusts asset-topology tests to new model + adds coverage for station split detection and materialization behavior.
packages/interfaces_pkg/tests/test_asset_topology_helpers.py	Updates helper tests to use MaterializedStation and RawStation and adds topology build helpers.
packages/interfaces_pkg/src/toop_engine_interfaces/stored_action_set.py	Switches action-set APIs to MaterializedStation and materializes from Topology when needed.
packages/interfaces_pkg/src/toop_engine_interfaces/asset_topology_helpers.py	Refactors helper functions to operate on MaterializedStation and adds RawStation support for connected-asset resolution.
packages/interfaces_pkg/README.md	Documents new raw_stations + materialize_stations() usage (naming needs adjustment).
packages/importer_pkg/tests/pypowsybl_import/test_preprocessing.py	Adds regression test for filtering split stations from relevant_subs.
packages/importer_pkg/tests/pandapower/test_preprocessing_pandapower.py	Updates pandapower preprocessing test to use a real Topology instance.
packages/importer_pkg/tests/pandapower/test_asset_topology_pandapower.py	Updates pandapower asset-topology tests for MaterializedStation/raw_stations.
packages/importer_pkg/tests/network_graph/test_powsybl_station_to_graph.py	Updates network-graph tests for MaterializedStation and materialized station counts.
packages/importer_pkg/tests/exporter/test_asset_topology_to_ucte.py	Updates exporter tests to use materialized stations (one test needs topology rebuild after mutation).
packages/importer_pkg/src/toop_engine_importer/pypowsybl_import/preprocessing.py	Filters split stations out of relevant_subs and reorders preprocessing steps to apply the filter before saving masks/N-1 definition.
packages/importer_pkg/src/toop_engine_importer/pypowsybl_import/init.py	Renames exported API symbol to get_raw_stations_and_assets.
packages/importer_pkg/src/toop_engine_importer/pandapower_import/preprocessing.py	Updates preprocess_net_step2 to rewrite raw_stations immutably via copy_topology_with_updates.
packages/importer_pkg/src/toop_engine_importer/pandapower_import/asset_topology.py	Builds Topology(raw_stations, assets, asset_bays) by canonicalizing station-derived payloads.
packages/importer_pkg/src/toop_engine_importer/network_graph/powsybl_station_to_graph.py	Produces Topology(raw_stations, assets, asset_bays) from materialized station extraction; adds busbar expansion logic.
packages/importer_pkg/src/toop_engine_importer/exporter/asset_topology_to_ucte.py	Exports using asset_topology.materialize_stations() and updates type hints to MaterializedStation.
packages/grid_helpers_pkg/tests/powsybl/test_powsybl_asset_topo.py	Updates powsybl helper tests for RawStation + canonical assets extraction.
packages/grid_helpers_pkg/src/toop_engine_grid_helpers/powsybl/powsybl_asset_topo.py	Refactors station extraction to return (raw_stations, topology_assets) and updates topology construction accordingly.
packages/grid_helpers_pkg/src/toop_engine_grid_helpers/powsybl/example_grids.py	Updates extracted topology generation to populate raw_stations, assets, and asset_bays.
packages/dc_solver_pkg/tests/test_example_grids.py	Updates assertions to use materialize_stations() counts.
packages/dc_solver_pkg/tests/preprocessing/test_write_aux_data.py	Switches monitored element counting to raw_stations.
packages/dc_solver_pkg/tests/preprocessing/test_realize_assignment.py	Updates station model references to MaterializedStation.
packages/dc_solver_pkg/tests/preprocessing/test_preprocess.py	Updates preprocessing tests to use raw_stations and topology copy helpers.
packages/dc_solver_pkg/tests/preprocessing/test_preprocess_switching.py	Updates switching preprocessing tests to use MaterializedStation and materialization calls.
packages/dc_solver_pkg/tests/preprocessing/test_preprocess_bb_outage.py	Updates outage preprocessing tests for MaterializedStation and realized-station usage.
packages/dc_solver_pkg/tests/postprocessing/test_apply_asset_topo_powsybl.py	Updates postprocess tests to use materialize_stations() and raw-station based topology copies.
packages/dc_solver_pkg/tests/postprocessing/test_apply_asset_topo_pandapower.py	Updates pandapower apply tests to use materialize_stations().
packages/dc_solver_pkg/tests/jax/test_busbar_outage.py	Refactors busbar-outage tests to use realized stations instead of deprecated assignment helpers.
packages/dc_solver_pkg/tests/export/test_station_switch_updates.py	Updates export tests to use materialized stations and raw-station topology copies.
packages/dc_solver_pkg/tests/export/test_export.py	Updates export tests to use materialized stations and raw-station topology copies.
packages/dc_solver_pkg/tests/export/test_disconnection_switch_updates.py	Updates disconnection export tests to use materialize_stations() and raw-station topology copies.
packages/dc_solver_pkg/tests/export/test_asset_topology_to_dgs.py	Updates DGS export tests to operate on materialized stations.
packages/dc_solver_pkg/tests/deprecated/assignment.py	Renames station type usage to MaterializedStation.
packages/dc_solver_pkg/tests/conftest.py	Updates fixtures to build MaterializedStation objects.
packages/dc_solver_pkg/src/toop_engine_dc_solver/preprocess/preprocess.py	Builds simplified topology via topology_from_materialized_stations and switches loops to materialize_stations().
packages/dc_solver_pkg/src/toop_engine_dc_solver/preprocess/preprocess_switching.py	Canonicalizes asset metadata updates via topology-level updates (copy_topology_with_updates).
packages/dc_solver_pkg/src/toop_engine_dc_solver/preprocess/preprocess_station_realisations.py	Updates injection aggregation to resolve assets from RawStation via topology-owned assets.
packages/dc_solver_pkg/src/toop_engine_dc_solver/preprocess/preprocess_bb_outage.py	Updates outage preprocessing to use materialized stations from topology.
packages/dc_solver_pkg/src/toop_engine_dc_solver/preprocess/network_data.py	Updates network-data validation + relevant-station selection to operate on raw_stations and MaterializedStation realizations.
packages/dc_solver_pkg/src/toop_engine_dc_solver/preprocess/action_set.py	Updates injection-topology computation to resolve assets from RawStation with topology assets.
packages/dc_solver_pkg/src/toop_engine_dc_solver/postprocess/realize_assignment.py	Updates postprocessing realization typing and validation to MaterializedStation.
packages/dc_solver_pkg/src/toop_engine_dc_solver/postprocess/postprocess_powsybl.py	Builds changed-station topology via topology_from_materialized_stations and fixes station-id lookup via raw_stations.
packages/dc_solver_pkg/src/toop_engine_dc_solver/postprocess/postprocess_pandapower.py	Switches realized-station type to AppliedStation and constructs realized topology via topology_from_materialized_stations.
packages/dc_solver_pkg/src/toop_engine_dc_solver/postprocess/apply_asset_topo_powsybl.py	Refactors powsybl application to accept (Topology, RawStation) and materialize internally when needed.
packages/dc_solver_pkg/src/toop_engine_dc_solver/postprocess/apply_asset_topo_pandapower.py	Updates pandapower apply path to use MaterializedStation + AppliedStation.
packages/dc_solver_pkg/src/toop_engine_dc_solver/export/station_switch_updates.py	Updates switching-diff export to use MaterializedStation and materialize_stations() for baselines.
packages/dc_solver_pkg/src/toop_engine_dc_solver/export/export.py	Updates export entry point typing and changed-station resolution for MaterializedStation.
packages/dc_solver_pkg/src/toop_engine_dc_solver/export/disconnection_switch_updates.py	Resolves disconnections against materialize_stations() output rather than topology.stations.
packages/dc_solver_pkg/src/toop_engine_dc_solver/example_grids.py	Builds random example topologies via topology_from_materialized_stations.
packages/dc_solver_pkg/src/toop_engine_dc_solver/example_classes.py	Updates example node-breaker topology JSON construction to new schema (raw_stations, canonical assets/asset_bays).
docs/interfaces/asset_topology.md	Updates documentation for the lean-topology model (class names still need alignment).
data/test_grid_node_breaker/initial_topology/asset_topology.json	Updates on-disk topology fixture to raw_stations + canonical assets/asset_bays schema.

Comments suppressed due to low confidence (1)

packages/importer_pkg/tests/exporter/test_asset_topology_to_ucte.py:579

• In this test, topology_stations = topology_model.materialize_stations() returns stations whose assets are deep-copied from topology_model.assets. Mutating topology_stations[0].assets[1].grid_model_id therefore does not update topology_model, so asset_topo_to_uct(asset_topology=topology_model, ...) won’t see the intended asset-id change. Rebuild topology_model from the mutated materialized stations before exporting.

[bpetrickNezk]

it is not clear to me how I get the Asset bay for:

1. we go to list[StationAssetConnection] e.g. in a station and get the switches
   does work, but looks also it can lead to some bugs if the order is wrong?
2. how do I get the two endpoints of a branch? I did not find this directly
   this is also in the StationAssetConnection? So one needs to loop over all connections to get the two that are relevant?

[sonarqube-mccs]

Quality Gate passed

Issues
18 New issues
1 Fixed issue
0 Accepted issues

Measures
0 Security Hotspots
91.9% Coverage on New Code
2.1% Duplication on New Code

See analysis details on SonarQube

[nicow-elia]

Some comments, I will look more into it tomorrow.

[nicow-elia]

Do we need anything in this file still?

[nicow-elia]

Maybe call it RealizedStation in line with RealizedTopology?

[nicow-elia]

I'd prefer it to have in the interface file only the model definition and validators and a heavy translation logic such as this one to live in another file. I would expect this logic to be bug-heavy and often changing, while hopefully the interface definition isn't

[nicow-elia]

So as I see it - the only difference between a raw station and a materialized station is that the materialized station has the AssetBay populated in the AssetConnections. I think it is a bit verbose to introduce a whole new station class for this, I'd rather say that we have an AssetConnection base model and two deriving classes MaterializedAssetConnection and Raw(currently Station)AssetConnection. The Station just has a list of AssetConnections and a property that does an isinstance check to find out if the asset bays have been populated?
This way I was just trying to get through Applied, Materialized and Raw Stations that all describe the same thing and I got lost a bit.