feat: initial KosmoConnect platform v0.1

Includes:
- Backend services: ingestion (:8001), weather API (:8002),
  gateway (:8003), billing (:8004) with BTCPay integration
- Shared asyncpg pool, TimescaleDB hypertable, Redis, Mosquitto MQTT
- React frontend: Dashboard (MapLibre) and Messaging (chat UI)
- Bridge daemon for Pi + Meshtastic (Serial/TCP T-Deck support)
- Production Docker Compose, Nginx reverse proxy, ops scripts
- DEPLOY.md with step-by-step deployment guide

backend/shared/db.py

@@ -0,0 +1,11 @@
+import os
+import asyncpg
+
+DB_DSN = os.getenv(
+    "DATABASE_URL",
+    "postgresql://kosmo:kosmo_dev_pass@localhost:5432/kosmoconnect"
+)
+
+
+async def get_pool() -> asyncpg.Pool:
+    return await asyncpg.create_pool(DB_DSN, min_size=2, max_size=10)

backend/shared/models.py

@@ -0,0 +1,46 @@
+from datetime import datetime
+from typing import Optional
+from pydantic import BaseModel, Field
+
+
+class EnviroReading(BaseModel):
+    time: datetime
+    node_id: str
+    temperature_c: Optional[float] = None
+    humidity_percent: Optional[float] = None
+    pressure_pa: Optional[float] = None
+    wind_speed_ms: Optional[float] = None
+    wind_direction: Optional[int] = None
+    pm25_ugm3: Optional[float] = None
+    pm10_ugm3: Optional[float] = None
+    gas_resistance_kohm: Optional[float] = None
+    battery_voltage: Optional[float] = None
+    solar_voltage: Optional[float] = None
+
+    class Config:
+        from_attributes = True
+
+
+class Node(BaseModel):
+    id: Optional[str] = None
+    mesh_node_id: str
+    name: Optional[str] = None
+    lat: Optional[float] = None
+    lon: Optional[float] = None
+    hardware_revision: str = "v1.0"
+    installed_at: Optional[datetime] = None
+    last_seen: Optional[datetime] = None
+    is_active: bool = True
+
+    class Config:
+        from_attributes = True
+
+
+class IngestEnviroPayload(BaseModel):
+    type: str = Field(default="enviro_reading")
+    node_id: str
+    received_at: datetime
+    hop_count: Optional[int] = None
+    lat: Optional[float] = None
+    lon: Optional[float] = None
+    payload: EnviroReading