Initial commit — DRB server stack

Includes c2-core (FastAPI/MQTT/Firestore), discord-bot (slash commands),
frontend (Next.js admin UI), and mosquitto config.

drb-c2-core/app/main.py

@@ -0,0 +1,44 @@
+import asyncio
+from contextlib import asynccontextmanager
+from fastapi import FastAPI, Depends
+from fastapi.middleware.cors import CORSMiddleware
+from app.internal.logger import logger
+from app.internal.mqtt_handler import mqtt_handler
+from app.internal.node_sweeper import sweeper_loop
+from app.internal.auth import require_firebase_token
+from app.routers import nodes, systems, calls, upload, tokens
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    logger.info("DRB C2 Core starting.")
+
+    await mqtt_handler.connect()
+    sweeper_task = asyncio.create_task(sweeper_loop())
+
+    yield  # --- app running ---
+
+    logger.info("DRB C2 Core shutting down.")
+    sweeper_task.cancel()
+    await mqtt_handler.disconnect()
+
+
+app = FastAPI(title="DRB C2 Core", lifespan=lifespan)
+
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+app.include_router(nodes.router,   dependencies=[Depends(require_firebase_token)])
+app.include_router(systems.router, dependencies=[Depends(require_firebase_token)])
+app.include_router(calls.router,   dependencies=[Depends(require_firebase_token)])
+app.include_router(tokens.router,  dependencies=[Depends(require_firebase_token)])
+app.include_router(upload.router)  # auth is per-node, handled inline
+
+
+@app.get("/health")
+async def health():
+    return {"ok": True, "mqtt_connected": mqtt_handler.is_connected}