Fix logging and surface unhandled exceptions

- basicConfig so the pops logger actually emits output
- Global exception handler logs full traceback + returns detail in 500

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

app/main.py

@@ -1,12 +1,17 @@
 import logging
 from contextlib import asynccontextmanager
 
-from fastapi import FastAPI
+from fastapi import FastAPI, Request
+from fastapi.responses import JSONResponse
 
 from app.db import check_db, run_migrations
 from app.routers import filaments, pricing, print_jobs, printers, todos
 from app.routers import ui
 
+logging.basicConfig(
+    level=logging.INFO,
+    format="%(asctime)s %(levelname)-8s %(name)s: %(message)s",
+)
 logger = logging.getLogger("pops")
 
 
@@ -18,7 +23,7 @@ async def lifespan(app: FastAPI):
         try:
             run_migrations()
         except Exception:
-            logger.exception("Migration failed — app will start but DB schema may be out of date")
+            logger.exception("Migration failed — schema may be out of date")
     else:
         logger.warning("Database unreachable: %s", msg)
     yield
@@ -26,6 +31,13 @@ async def lifespan(app: FastAPI):
 
 app = FastAPI(title="POPS", lifespan=lifespan)
 
+
+@app.exception_handler(Exception)
+async def unhandled_exception(request: Request, exc: Exception):
+    logger.exception("Unhandled error on %s %s", request.method, request.url)
+    return JSONResponse(status_code=500, content={"detail": str(exc)})
+
+
 # JSON API
 app.include_router(printers.router, prefix="/api")
 app.include_router(filaments.router, prefix="/api")
@@ -33,7 +45,7 @@ app.include_router(print_jobs.router, prefix="/api")
 app.include_router(todos.router, prefix="/api")
 app.include_router(pricing.router, prefix="/api")
 
-# Web UI (must come after API to avoid route shadowing)
+# Web UI
 app.include_router(ui.router)