feat(plugins): add read-only multi-instance E64 sensor

doc/Api.md

@@ -213,10 +213,10 @@ move a consumer's cursor backwards.
 ### Steams
 
 Recorded milk-steaming sessions. Each record is opened when the machine
-enters `steam` and finalized when it leaves. Today no probe is wired in
-production, so `SteamSnapshot.milkTemperature` is `null` on every frame —
-the API surface is scaffolding for skin developers and for future
-probe / FW support. `SteamSettings.stopAtTemperature` (in
+enters `steam` and finalized when it leaves. `SteamSnapshot.milkTemperature`
+uses the preferred Bengle milk probe when its declared temperature channel is
+available, and is `null` when no suitable sensor is registered.
+`SteamSettings.stopAtTemperature` (in
 `/api/v1/workflow`) is the target the future FW-autonomous stop or
 in-app stop will trigger on.
 

examples/plugins/e64ws.reaplugin/README.md

@@ -0,0 +1,43 @@
+# E64 WebSocket sensor
+
+This opt-in example exposes one read-only sensor registration per configured
+Mahlkoenig E64 grinder. It uses the existing host WebSocket transport and
+publishes the complete driver state as the `state` object channel.
+
+Use an ordinary setting for the instance list and the secure setting for the
+tokens. Set `InstancesJson` to this JSON:
+
+```json
+[{"id":"e64-one","name":"Kitchen E64","scheme":"ws","host":"127.0.0.1","port":9997,"pollMs":1000}]
+```
+
+Set `TokensJson` to this JSON:
+
+```json
+{"e64-one":"replace-with-the-secure-session-token"}
+```
+
+Each instance needs a unique safe id, a non-empty name, `ws` or `wss`, a
+hostname or bracketed valid IPv6 address, a port from 1 through 65535, and a
+token. DNS labels cannot be empty or start/end with a hyphen. Malformed IPv6
+literals such as `[.]`, `::::`, and `[12345::1]` are rejected.
+At most eight instances are accepted. `pollMs` is optional: `0` disables
+polling, otherwise it must be between 100 and 3,600,000 milliseconds. The
+whole configuration is checked before any sensor registration or socket open;
+an unknown token id or any invalid entry rejects the complete load.
+
+The four exposed reads send only `RequestDriverState`, `RequestDriverConfig`,
+`RequestNachineInfo`, and `RequestLogMessages`. The plugin has no motor,
+configuration, calibration, or GBS write path. A device disconnect affects its
+own instance. A settings reload is a whole-plugin operation and may reconnect
+all configured instances; it is the supported way to change the list.
+
+The corresponding result types are `RequestDriverStateResult`,
+`RequestDriverConfigResult`, `RequestNachineInfoResult`, and
+`RequestLogMessagesResult`. Results must carry the matching `refId`; the
+documented JSON `pong` heartbeat is ignored and never published.
+
+`ws` is suitable for a trusted network or a loopback fixture. `wss` uses the
+platform's trusted TLS certificates and does not bypass certificate checks.
+This example has been validated with the loopback simulator; it does not claim
+hardware validation.

examples/plugins/e64ws.reaplugin/manifest.json

@@ -0,0 +1,26 @@
+{
+  "id": "e64ws.reaplugin",
+  "name": "Mahlkoenig E64 WebSocket Sensor",
+  "author": "Decaid contributors",
+  "description": "Opt-in read-only E64 telemetry over the local WebSocket protocol.",
+  "version": "0.1.0",
+  "apiVersion": 1,
+  "permissions": ["network.websocket"],
+  "drivers": [{"id": "e64ws", "type": "sensor"}],
+  "settings": {
+    "InstancesJson": {
+      "type": "string",
+      "label": "E64 instances",
+      "description": "JSON array of grinder id, name, scheme, host, port, and optional pollMs values.",
+      "default": "[]"
+    },
+    "TokensJson": {
+      "type": "string",
+      "label": "E64 session tokens",
+      "description": "JSON object mapping each configured grinder id to its WebSocket session token.",
+      "secure": true,
+      "default": "{}"
+    }
+  },
+  "api": []
+}