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>

api-docs/lrpr.md

@@ -0,0 +1,66 @@
+# LRPR — Filter Pressure Sensor (LRPR-0D6800)
+
+**Module ID**: `6a17218be0b88ea3e925524f`  
+**Serial**: `1D00010D68000001`  
+**MAC**: `C8:B9:61:0D:68:00`  
+**UUID**: `1D0058B9610D680000000001000D6800`  
+**Firmware**: 6.3.0 | **Hardware**: A | **Manufacturer**: `1D`  
+**Type**: `lr-pr`  
+**Role**: Measures filter pressure — indicates filter cleanliness / pump running state
+
+---
+
+## Input
+
+| Input ID | Type | Unit | Interval |
+|---|---|---|---|
+| `6a17218be0b88ea3e9255251` | 8 (pressure) | bar (unit code 6) | 1 min |
+
+Raw-to-bar expression: `(1.5 × raw − 500) / 1000`
+
+### Latest readings (2026-06-04)
+
+```
+16:01  0.091 bar  ← pump stopped / off
+16:00  0.715 bar
+15:59  0.741 bar
+15:58  0.730 bar
+18:41  0.081 bar  ← pump off
+```
+
+Normal operating pressure ~0.70–0.75 bar. Drop to ~0.08 bar signals pump has stopped.  
+This sensor can be used to detect filtration start/stop and detect dirty filter (rising pressure).
+
+---
+
+## Remote state
+
+- Battery: **94%**
+- Last radio contact: 2026-06-04T20:05:14Z
+- Relay: `60ca4276ad69dac1558f7c61` (LRMB10)
+- No programs, no outputs — pure sensor
+
+---
+
+## Pressure Alert Configuration
+
+From `poolPressureAlertsVariables` in the input object (retrieved via mobile API):
+
+| Parameter | Value | Meaning |
+|---|---|---|
+| `staticPressure` | 0.919 bar | Baseline pressure at pump start |
+| `nominalPressure` | 1.7275 bar | Expected operating pressure |
+| `maximalPressure` | 1.0615 bar | Upper alert threshold |
+| `atmosphericPressure` | 1.015 bar | Calibration reference |
+| `filterCloggedMargin` | 0.5 bar | Rise above static = filter clogged alert |
+| `filterPreCloggedMargin` | 0.3 bar | Rise above static = pre-clog warning |
+| `activeFilterCloggedAlert` | true | Filter clog alert enabled |
+| `activeWaterLevelLowAlert` | true | Low water level alert enabled |
+| `activeSuctionValveClosedAlert` | true | Suction valve closed alert enabled |
+| `waterLevelLowCount` | 6 | Ticks below threshold before alert |
+
+## Notes
+
+- `secondaryBatteryVoltage: 80` — secondary power source present
+- Unit code 6 = bar; type 8 = pressure sensor
+- Backwash reminder alerts fire every ~15 days (shared with pool notebook)