Phase 0.1: Remove backend deprecated code

- Delete routes: counter.py, sum.py
- Delete jobs.py and worker.py
- Delete tests: test_counter.py, test_jobs.py
- Update audit.py: keep only price-history endpoints
- Update models.py: remove VIEW_COUNTER, INCREMENT_COUNTER, USE_SUM permissions
- Update models.py: remove Counter, SumRecord, CounterRecord, RandomNumberOutcome models
- Update schemas.py: remove sum/counter related schemas
- Update main.py: remove deleted router imports
- Update test_permissions.py: remove tests for deprecated features
- Update test_price_history.py: remove worker-related tests
- Update conftest.py: remove mock_enqueue_job fixture
- Update auth.py: fix example in docstring

backend/main.py

@@ -6,16 +6,13 @@ from fastapi import FastAPI
 from fastapi.middleware.cors import CORSMiddleware
 
 from database import Base, engine
-from jobs import close_job_pool
 from routes import audit as audit_routes
 from routes import auth as auth_routes
 from routes import availability as availability_routes
 from routes import booking as booking_routes
-from routes import counter as counter_routes
 from routes import invites as invites_routes
 from routes import meta as meta_routes
 from routes import profile as profile_routes
-from routes import sum as sum_routes
 from validate_constants import validate_shared_constants
 
 
@@ -28,8 +25,6 @@ async def lifespan(app: FastAPI):
     async with engine.begin() as conn:
         await conn.run_sync(Base.metadata.create_all)
     yield
-    # Cleanup on shutdown
-    await close_job_pool()
 
 
 app = FastAPI(lifespan=lifespan)
@@ -44,8 +39,6 @@ app.add_middleware(
 
 # Include routers - modules with single router
 app.include_router(auth_routes.router)
-app.include_router(sum_routes.router)
-app.include_router(counter_routes.router)
 app.include_router(audit_routes.router)
 app.include_router(profile_routes.router)
 app.include_router(availability_routes.router)