feat(firmware): validate configuration and migrate sensor-driven flight APIs

Validate configuration through its owning schemas and keep board
declarations separate from shared F722 resource ownership. Bound USB
transitions, isolate transport failures and retain restart-only activation.

Migrate navigation and flight consumers with the sensor and schema
contracts. Require explicit installation data and synchronous output
authority; board motor outputs remain inhibited.

Validation: assembled-prefix host tests, strict Clippy, platform/USB tests
and both ARM release builds. Final-source coverage and scoped Miri/Kani
evidence are retained separately from hardware qualification.

firmware/libs/kaptan-mavlink/definitions/publish/imu.xml

@@ -4,10 +4,10 @@
   <dialect>0</dialect>
   <messages>
     <message id="51028" name="IMU">
-      <description>One accepted body-frame inertial observation in the native bounded sensor representation.</description>
+      <description>Body-frame inertial observation. Payload offsets are time_us 0, angular_rate 8, acceleration 20 and temperature 26. Payload length is 28 bytes, extra CRC 22.</description>
       <field type="uint64_t" name="time_us">Flight-controller monotonic acquisition time in microseconds.</field>
       <field type="int16_t[3]" name="acceleration_milligravity">Body-frame acceleration in milligravity.</field>
-      <field type="int16_t[3]" name="angular_rate_milliradians_per_second">Body-frame angular rate in milliradians per second.</field>
+      <field type="int32_t[3]" name="angular_rate_milliradians_per_second">Body-frame angular rate in milliradians per second. Preserves the full MPU6000 plus or minus 2000 degrees per second decoded range.</field>
       <field type="int16_t" name="temperature_centidegrees_celsius">Sensor temperature in centidegrees Celsius.</field>
     </message>
   </messages>