refactor: reorganize interview files and fix errors

Changes:
- Fixed CAP theory typo: "CP、AP、AP" → "CP、AP、CA"
- Reorganized file classifications for better structure:
  * Moved 4 database-related files from 01-分布式系统 to 02-数据库
  * Moved ConcurrentHashMap from 03-缓存 to 05-并发编程
  * Renamed 消息队列（RocketMQ_Kafka）.md → 消息队列_RocketMQ_Kafka.md
- Updated project overview with new structure (73 files, 15 categories)
- Database category now has 6 files (more cohesive)
- Concurrency category now has 5 files (better organized)

File movements:
- 事务隔离级别.md: 01-分布式系统 → 02-数据库
- 数据库锁机制.md: 01-分布式系统 → 02-数据库
- 分库分表.md: 01-分布式系统 → 02-数据库
- MySQL主从延迟.md: 01-分布式系统 → 02-数据库
- ConcurrentHashMap原理.md: 03-缓存 → 05-并发编程

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

questions/01-分布式系统/CAP理论和BASE理论.md

@@ -4,7 +4,7 @@
 
 1. 什么是 CAP 理论？CAP 三者为什么不可兼得？
 2. 什么是 BASE 理论？
-3. CP、AP、AP 架构分别适用于什么场景？
+3. CP、AP、CA 架构分别适用于什么场景？
 4. Zookeeper、Eureka、Nacos、Consul 分别是 CP 还是 AP？
 5. 在实际项目中如何权衡一致性、可用性、分区容错性？