- Fixed bug where daily quota counts weren't resetting on new day
(if_not_exists only works for missing attributes, not day changes)
- Changed to two-phase approach: reset if new day, then increment
- Added QUOTA_TIMEZONE env var for local midnight reset (e.g., Asia/Tokyo)
- Added timezone validation with UTC fallback
- Add dynamo-quota-manager.ts for atomic quota checks using ConditionExpression
- Enforce daily request limit, daily token limit, and TPM limit
- Return 429 with quota details (type, used, limit) when exceeded
- Quota is opt-in: only enabled when DYNAMODB_QUOTA_TABLE env var is set
- Remove client-side quota enforcement (server is now source of truth)
- Simplify use-quota-manager.tsx to only display toasts
- Add @aws-sdk/client-dynamodb dependency
