LeetCode 739: Daily Temperatures

## [LeetCode 739: Daily Temperatures](https://leetcode.com/problems/daily-temperatures/)

**Difficulty:** Medium
**Category:** Monotonic Stack

### Tasks
- [ ] Implement solution in `src/monotonic_stack/daily_temperatures.py`
- [ ] Verify tests pass: `pytest tests/test_daily_temperatures.py`
- [ ] Analyze time and space complexity