Add thresholded trigger count acquisition (SE-422)

Explanation of changes

Add a new acquisition protocol ThresholdedTriggerCount, which allows conditional playback with a trigger count acquisition on Qblox QTM or QRM modules.

Usage:

schedule = Schedule("example")

schedule.add(ThresholdedTriggerCount(
            port="qe0:optical_readout",
            clock="qe0.ge0",
            duration=10e-6,
            threshold=10,
            feedback_trigger_label="qe0",
            feedback_trigger_condition=TriggerCondition.GREATER_EQUAL,
        )
)

sub_schedule = ...

schedule.add(ConditionalOperation(body=sub_schedule, qubit_name="qe0"), rel_time=...)

To do in follow-up MRs:

• more documentation (e.g. for usage with ConditionalOperation)
• gate-level NV center support

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Merge checklist

See also merge request guidelines

• Merge request has been reviewed (in-depth by a knowledgeable contributor), and is approved by a project maintainer.
• New code is covered by unit tests (or N/A).
• New code is documented and docstrings use numpydoc format (or N/A).
• New functionality: considered making private instead of extending public API (or N/A).
• Public API changed: added @deprecated and entry in deprecated code suggestions (or N/A).
• Newly added/adjusted documentation and docstrings render properly (or N/A).
• Pipeline fix or dependency update: post in #software-for-developers channel to merge main back in or update local packages (or N/A).
• Tested on hardware (or N/A).
• CHANGELOG.md for breaking changes and AUTHORS.md have been updated (or N/A).
• Update Hardware backends documentation if backend interface change or N/A
• Check whether performance is significantly affected by looking at the Performance metrics results.
• Windows tests in CI pipeline pass (manually triggered by maintainers before merging).
  • Maintainers do not hit Auto-merge, we need to actively check as manual tests do not block pipeline

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For reference, the issues workflow is described in the contribution guidelines.