Orca MM Runner

[MattBurn]

Closes Issues

Closes #185

Description

Extracts shared ORCA execution logic from Runner into a new BaseRunner and adds OrcaMmRunner in opi.execution.mm for running orca_mm.

OrcaMmRunner adds typed helpers for supported orca_mm subcommands, validates expected output files, and raises a dedicated OrcaMmException when orca_mm reports errors on stderr. This also extends OrcaBinary with ORCA_MM and adds unit coverage for stderr handling, including the empty/deleted temporary stderr-file case.

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Release Notes

Added

• Added BaseRunner to share ORCA binary resolution, environment setup, version checks, and subprocess execution across runner implementations. (Orca MM Runner #224)
• Added OrcaMmRunner with helpers for orca_mm commands such as convff, splitff, mergeff, repeatff, splitpdb, mergepdb, makeff, and getHDist. (Orca MM Runner #224)
• Added OrcaBinary.ORCA_MM and unit tests covering orca_mm stderr handling. (Orca MM Runner #224)

Changed

• Changed Runner to inherit from BaseRunner, keeping orca, orca_plot, and orca_2json behavior while moving shared execution logic into the base class. (Orca MM Runner #224)