docs: document board configuration workflow

docs/src/errors.md

@@ -28,12 +28,13 @@ for safety state, actuator inhibit, or typed configuration results.
   rule, and protocol error code.
 - Runtime driver and link faults reach the F722 MAVLink worker as a
   `KAPTAN_ERROR` path, subject to bounded transport admission. The error
-  payload is `{ flags, path_length, additional_information_length, path[96],
-  additional_information[64] }`; each length identifies the valid UTF-8
-  prefix and the optional information field may be empty. A `KaptanError`
-  derive supplies the type/variant path and normally leaves additional
-  information empty. `log::error!` uses the Rust log target as the path and
-  the formatted message as additional information.
+  payload is `{ level, flags, path_length, additional_information_length,
+  path[96], additional_information[64] }`; `level` preserves the originating
+  MAVLink-compatible severity from Emergency through Error, each length
+  identifies the valid UTF-8 prefix, and the optional information field may be
+  empty. A `KaptanError` derive supplies the type/variant path and normally
+  leaves additional information empty. `log::error!` uses the Rust log target
+  as the path and the formatted message as additional information.
 - A rejected configuration operation may enqueue a companion `KAPTAN_ERROR`
   whose path is the high-level `ProtocolError` identity. It is intentionally
   not correlated and carries no field/rule detail; the matching