mocap: add reset_counter and estimator fields to mocap messages

[alireza787b]

Summary

This is a clean replacement for the earlier mocap proto attempt.

It adds the missing additive fields that the downstream MAVSDK mocap implementation needs for external-vision / mocap EKF integration, while keeping the MAVLink frame mapping in C++.

Changes

• add VisionPositionEstimate.reset_counter
• add VisionSpeedEstimate.reset_counter
• add Odometry.reset_counter
• add Odometry.MavEstimatorType
• add Odometry.estimator_type
• add Odometry.quality_percent
• clarify Odometry.MavFrame comments without changing the protobuf enum numbering

Why this shape

• frame mapping stays in C++, as discussed in mocap: fix MavFrame enum values to match MAVLink specification #396
• this keeps the proto change additive and minimal
• the downstream MAVSDK follow-up can then update the submodule, regenerate mocap bindings, and wire the fields cleanly

Notes

• the earlier proto attempt did not include VisionSpeedEstimate.reset_counter
• this PR intentionally does not revive the enum-value approach from mocap: fix MavFrame enum values to match MAVLink specification #396

Follow-up

• MAVSDK follow-up PR to update the submodule, regenerate mocap bindings, and wire the fields

[julianoes]

I think that's sane.