The module: Ground Control's library on Zephyr, with one worker thread

Ground Control's RockBLOCK 9704 library is pinned untouched in west.yml
and compiled here for any board with a UART: a serial port on the bus of
the rock7,rockblock-9704 devicetree node, the library's timing calls on
the kernel, and one worker thread that owns every call into it, since the
library has no locking and shares static buffers.

The worker sleeps until a request or a byte from the modem arrives.
Requests (begin, end, power, send, info, signal) wait as long as the
caller says; a send with K_NO_WAIT queues and reports through mo_done.
Callbacks for a sent message, a received one, the signal and the
provisioning; a status snapshot that never touches the modem.

The library asks for provisioning once and keeps a miss for good; the
worker clears its cache before a send whose topic is missing and after
the modem refuses one, so a modem provisioned later is seen.

The serial port and worker began in the OGLAS satellite bench and were
carried through WII6's lib/wii6-sat.

LICENSE

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+MIT License
+
+Copyright (c) 2026 Scott Penrose
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.