Normalized rate limit configuration with all optional fields resolved to concrete values.

Produced by normalizeRuntimeConfig from the user-provided RateLimitConfig. Guarantees that all fields are present and validated, safe for direct use by SlidingWindowRateLimiter.

interface NormalizedRateLimitConfig {
    enabled: boolean;
    scope: 'user' | 'conversation' | 'user-or-conversation';
    windowMs: number;
    maxRequests: number;
}