Add gyroscope.v1

> **Scope narrowed.** The Android field-matrix and real-device evidence regime has been
> removed from this issue. What remains is the work that a build, a test, or a checked-in
> artifact can settle.

## Summary

Add a dedicated `gyroscope.v1` Android collector for raw angular-velocity observations.

The collector records sensor observations only. It must not calculate orientation, activity, gestures, or behavioral inferences.

## Requirements

### Schema and configuration

- Define a registry entry and compiled collector module for Android's calibrated gyroscope source.
- Record:
- raw x/y/z angular velocity in radians per second;
- the hardware/source continuous-monotonic timestamp;
- sensor accuracy using a strict enum;
- any source metadata required to interpret timestamp/accuracy without identifying the physical device.
- Preserve the sensor's coordinate-system semantics in the catalog and documentation.
- Use the same bounded sampling-period and maximum-report-latency model as the accelerometer collector, expressed as integer physical-unit configuration values under Protocol v1.
- Define absolute minimum/maximum sampling, batch latency, encoded-event-size, rate, daily-volume, and quota bounds.
- Reject unsupported or unavailable required hardware before enrollment; do not substitute another motion sensor.

### Runtime behavior

- Use the shared collector lifecycle, access, clock, event-sink, backpressure, and quota contracts.
- Register/unregister the sensor listener idempotently across start, pause, resume, process recovery, finish, and withdraw.
- Enforce the pause/withdraw barrier so no callback accepted after the barrier can be appended.
- Preserve source timestamps rather than replacing them with callback wall time; attach the standard wall/boot context required by Protocol v1.
- Bound callback queues and batching. On overflow, quota, unavailable sensor, or OS failure, emit only bounded fixed-code collector state/audit events.
- Do not add filesystem, database, network, arbitrary logging, inference, or export logic.

### Integration and assurance

- Add Web configuration controls, required-hardware validation, researcher/participant disclosure, data-dictionary entries, Python decoder, Parquet schema/fixtures, and demo/test configuration.
- Document device-dependent range, resolution, calibration, batching, and achieved-rate differences without claiming cross-device equivalence.

## Acceptance criteria

- Valid x/y/z, timestamp, and accuracy events round-trip through storage, manual export, automatic upload, Python verification, and typed Parquet.
- Requested sampling period and report latency are strictly bounded and map deterministically to Android sensor registration.
- Hardware timestamps remain ordered only within their documented boot-session/source-clock domain.
- Missing required hardware blocks enrollment; an optional unavailable collector follows the explicit Protocol v1 behavior without substitution.
- Pause, resume, rapid lifecycle changes, process death, reboot, listener errors, queue pressure, and quota have deterministic tests.
- No event is appended after the pause/withdraw barrier.
- Maximum encoded event size and configured rate bounds are enforced before append.
- No production code or documentation performs or claims orientation/activity inference.

## Documentation

Update the catalog, collector guide, researcher/participant guides, consent copy, data dictionary, coordinate/time semantics, threat model, device-variance guidance, and analysis examples.

## Dependencies

Blocked by #10 and #11.

Start with the existing accelerometer collector and the shared Protocol v1 lifecycle, access, clock, event-sink, backpressure, and quota contracts. Trace the Web configuration, Python decoder, Parquet schema and fixtures, catalog, and demo/test configuration mentioned in the issue. Done means bounded gyroscope events round-trip through storage and export, required hardware and lifecycle behavior are tested, and the listed documentation is updated without inference logic.

Written by the indexing model from the issue text.