feat: implement local authentication flow and update related tests

backend/.env.test

@@ -0,0 +1,38 @@
+# Commit-safe backend test environment.
+# Usage:
+#   cd backend
+#   uv run --env-file .env.test uvicorn app.main:app --reload --port 8000
+
+ENVIRONMENT=dev
+LOG_LEVEL=INFO
+LOG_FORMAT=text
+LOG_USE_UTC=false
+REQUEST_LOG_SLOW_MS=1000
+REQUEST_LOG_INCLUDE_HEALTH=false
+
+# Local backend -> local Postgres (adjust host/port if needed)
+DATABASE_URL=postgresql+psycopg://postgres:postgres@localhost:5432/mission_control_test
+CORS_ORIGINS=http://localhost:3000
+BASE_URL=
+
+# Auth mode: local for test/dev
+AUTH_MODE=local
+# Must be non-placeholder and >= 50 chars
+LOCAL_AUTH_TOKEN=test-local-token-0123456789-0123456789-0123456789x
+
+# Clerk settings kept empty in local auth mode
+CLERK_SECRET_KEY=
+CLERK_API_URL=https://api.clerk.com
+CLERK_VERIFY_IAT=true
+CLERK_LEEWAY=10.0
+
+# Database
+DB_AUTO_MIGRATE=true
+
+# Queue / dispatch
+RQ_REDIS_URL=redis://localhost:6379/0
+RQ_QUEUE_NAME=default
+RQ_DISPATCH_THROTTLE_SECONDS=15.0
+RQ_DISPATCH_MAX_RETRIES=3
+
+GATEWAY_MIN_VERSION=2026.02.9