feat: initial myprimal MQTT bridge service

Dynamic MySolem/MyIndygo IoT bridge with MQTT, Home Assistant
autodiscovery, and Homebridge EasyMQTT compatibility.

- Device discovery via MySolem API on startup (all modules/inputs/outputs)
- Configurable poll engine (fast/normal/slow buckets, per-input overrides)
- MQTT retained state publishing + HA autodiscovery payloads
- Unified manual command routing (linesControl vs sendManualModuleCommand)
- Runtime config via MQTT $config/set, persisted to config.json
- Expression override system (API-provided > hardcoded > passthrough)
- Minimal REST API: /health, /state, /control, /rediscover
- Docker deployment (Dockerfile + docker-compose.yml)
- 38 unit tests

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

CLAUDE.md

@@ -0,0 +1,36 @@
+# myprimal
+
+Reverse-engineered client for the MySolem irrigation platform.
+
+## Goal
+
+Fetch sensor telemetry and control IoT devices (valves, stations) by talking directly to the MySolem backend.
+
+## Target environment
+
+**Base URL**: `https://qualif.mysolem.com` (qualification environment — always use this, not www.mysolem.com)
+
+## Project layout
+
+```
+api-docs/          # Reverse-engineered API documentation
+  overview.md      # Auth, architecture, key IDs
+  endpoints.md     # All discovered endpoints
+  control.md       # Device control commands
+```
+
+## Auth
+
+Session-cookie based (Sails.js). Call `POST /login` with form data, keep the cookie jar for all subsequent requests. See `api-docs/overview.md`.
+
+## Key account IDs
+
+- User ID: `5de53bca7ed4c45c2cfe067f`
+- Site ID (Domicile): `62b30d26ecbceb08607592c1`
+- Soil moisture input ID: `60ca42adad69dac1558f7c66`
+
+## Notes
+
+- Backend: Node.js + Sails.js, MongoDB ObjectIds
+- Real-time updates via socket.io, but all read/write ops also work over plain HTTP
+- No CSRF enforcement on JSON endpoints