✨ Expose QDMI queue length and job position - #2010

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Description

Expose QDMI queue inspection generically through MQT Core:

• Device::getQueueLength() -> std::optional<size_t> and Device.queue_length() -> int | None
• Job::getQueuePosition() -> std::optional<size_t> and the Python Job.queue_position property
• client-to-device property forwarding in the QDMI driver
• the minimal low-level QDMI client-driver support for retrieving an existing job by ID required by the merged QDMI API

Unsupported device properties remain valid and return an empty optional/None. Queue-position state or provider errors remain errors, so consumers can distinguish an unsupported measurement from a job that is no longer queued. DDSIM deliberately reports both properties as unsupported rather than inventing queue data.

QDMI #485 and QDMI #486 are merged. This PR pins the validated QDMI develop revision e80020f7 containing both APIs.

Relationship to #2008

This PR owns queue inspection and the low-level retrieval compatibility path needed to consume the merged QDMI ABI: optional provider-symbol loading, the exported C entry point, driver-owned job wrapping/lifetime management, and its contract tests.

Core #2008 remains the follow-up for the public FoMaC Device::retrieveJobById and Python retrieve_job_by_id APIs, their bindings/documentation/tests, and explicit entry points for current built-in providers where appropriate. Once this PR merges, #2008 can be rebased onto current main and reduced to that distinct surface, removing its now-duplicated low-level plumbing and QDMI pin update.

Validation

• complete release build (596 targets)
• native FoMaC suite (268/268 passed)
• native QDMI driver suite (118/118 passed)
• native DDSIM device suite (47/47 passed)
• focused Python queue tests (6/6 passed)
• generated Python stubs
• full repository nox -s lint
• focused retrieval tests after the clang-tidy remediation (4/4 passed)

Checklist

• The pull request only contains commits that are focused and relevant to this change.
• I have added appropriate tests that cover the new/changed functionality.
• I have updated the documentation to reflect these changes.
• I have added entries to the changelog for any noteworthy additions, changes, fixes, or removals.
• I have added migration instructions to the upgrade guide (not needed).
• The changes follow the project's style guidelines and introduce no new warnings.
• The changes are fully tested and pass the local checks.
• I have reviewed my own code changes.

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