obd-poller over the K-line via the Bluetooth ELM327; gnss publisher; elm_connected

obd-poller drops its CAN socket: the Z27AG answers OBD-II only on ISO 9141-2.
It holds a raw RFCOMM link to the ELM (no pairing, no root), fixes the protocol
(ATSP3) so nothing probes CAN, publishes the obd_* signals, and releases the
adapter after a minute of ECU silence so it can sleep.
gnss: gpsd's fix as yukart/gnss/<signal>. orin-status: elm_connected from BlueZ.
One native deploy script (deploy-native.sh BIN) behind the per-service ones;
/etc/default/yukart-elm holds the adapter's address.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DDwfd6Ki8UfG4hK6W5YpJz

deploy/yukart-elm.default

@@ -0,0 +1,5 @@
+# The ELM327 (OBD-II on the K-line, over Bluetooth serial): its address, read by
+# yukart-obd-poller (which connects) and yukart-orin-status (which only watches).
+# Installed to /etc/default/yukart-elm by scripts/deploy-native.sh when absent;
+# edit it there for another adapter, then restart both services.
+ELM_ADDR=00:0C:BF:50:AF:3F

deploy/yukart-gnss.service

@@ -0,0 +1,15 @@
+[Unit]
+Description=Yukart gnss: the receiver's fix on the bus, as single values
+Documentation=gitea:yukart/svc-core
+# Tier 2. Ordered after the broker and gpsd; it reconnects to either by itself.
+After=mosquitto.service gpsd.service
+StartLimitIntervalSec=0
+
+[Service]
+User=mikkeli
+ExecStart=/usr/local/bin/yukart-gnss
+Restart=always
+RestartSec=2
+
+[Install]
+WantedBy=multi-user.target

deploy/yukart-obd-poller.service

@@ -1,14 +1,15 @@
 [Unit]
-Description=Yukart obd-poller: OBD-II mode 01 polling, the single CAN writer
+Description=Yukart obd-poller: OBD-II over the K-line through the Bluetooth ELM327
 Documentation=gitea:yukart/svc-core
-# Tier 2. Ordered after the broker and nothing else: the adapter comes and goes, and
-# the poller only sends while the bus is visibly alive.
-After=mosquitto.service
+# Tier 2. Ordered after the broker and Bluetooth: the adapter comes and goes, and the
+# poller connects, releases and retries by itself.
+After=mosquitto.service bluetooth.service
 StartLimitIntervalSec=0
 
 [Service]
 User=mikkeli
-ExecStart=/usr/local/bin/yukart-obd-poller
+EnvironmentFile=/etc/default/yukart-elm
+ExecStart=/usr/local/bin/yukart-obd-poller --elm ${ELM_ADDR}
 Restart=always
 RestartSec=2
 

deploy/yukart-orin-status.service

@@ -9,7 +9,9 @@ StartLimitIntervalSec=0
 User=mikkeli
 # The UPS INA219 is on /dev/i2c-7, group i2c.
 SupplementaryGroups=i2c
-ExecStart=/usr/local/bin/yukart-orin-status
+# The ELM's address, for elm_connected; without the file nothing is reported.
+EnvironmentFile=-/etc/default/yukart-elm
+ExecStart=/usr/local/bin/yukart-orin-status --elm ${ELM_ADDR}
 Restart=always
 RestartSec=2