Add measured room impulse response providers

[Akinesia112]

Summary

• add native MRTD SingleRoomSRIR acquisition with semantic environment, receiver, and loudspeaker parameters
• add raw-provider adapters for Arni, MIT IR Survey, MOTUS, BUT ReverbDB, ACE Challenge, and OpenAIR
• support verified source URLs and explicit local source paths without inventing DOI or spatial metadata
• preserve provider channels and provenance for non-SOFA corpora

Scope

MRTD completes the native SOFA pipeline. MOTUS, ACE, and the listed OpenAIR environments support automatic raw acquisition. Arni, MIT, and BUT use explicit local source paths where stable/versioned automatic acquisition or licensing is unavailable. Raw-only adapters deliberately do not guess source/receiver coordinates or collapse multichannel data.

Validation

• ruff format --check: passed
• ruff check: passed
• pytest: 72 passed
• MRTD public get() validated with a downloaded offices_kemar_ls_1.sofa file against SingleRoomSRIR v1.0

[artpelling]

Hi @Akinesia112 thanks for contributing! I know this is still a draft. I've reviewed your code a bit and most of it looks like a worthwhile addition to irdl. To make the review more manageable, would you be willing to split this up into multiple smaller PRs?

We could start with MRTD. For the raw-only datasets, I would need some time to think about how to handle those.