feat: v1.1.0 - MAC protocol, CLI tool, extended markets, unified client

- Add MacClient/AsyncMacClient with full MAC protocol support (quotes, kline
  with adjustment, tick charts, transactions, boards, capital flow, auction,
  unusual, symbol info, server info)
- Add MacExClient/AsyncMacExClient for extended markets (HK, US, futures)
- Add UnifiedTdxClient auto-routing between A-share and extended markets
- Add `easy-tdx` CLI tool with JSON default output, Agent-friendly
- Add field bitmap protocol for custom quote field selection
- Fix quote-list missing fields (default to BASIC+VOLUME preset)
- Add config.py with centralized host management and auto-discovery
- Add 50+ examples covering all APIs (01-20)
- Rewrite README with CLI-first, Agent-friendly documentation
- Bump version to 1.1.0

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

examples/02_market_info/security_count.py

@@ -1,9 +1,30 @@
-"""演示：获取市场证券总数。"""
+"""演示：获取市场证券总数。
 
-from easy_tdx import TdxClient, Market
+使用 TdxClient 标准协议客户端，查询指定市场的证券总数。
+Market 枚举: SH=1(上海), SZ=0(深圳), BJ=2(北京)
+
+Market 枚举说明：
+  Market.SZ = 0  -- 深圳证券交易所（深市主板、中小板、创业板）
+  Market.SH = 1  -- 上海证券交易所（沪市主板、科创板）
+  Market.BJ = 2  -- 北京证券交易所（北交所，原新三板精选层）
+
+返回: int -- 证券总数（含股票、基金、债券、指数等所有品种）
+
+注意: Market.BJ 的结果可能不稳定（服务器端问题），不建议在生产中依赖。
+
+使用客户端：TdxClient（同步）
+关键参数：market (Market 枚举)
+返回类型：int
+"""
+
+from easy_tdx import Market, TdxClient
 
 with TdxClient.from_best_host() as c:
     sh_count = c.get_security_count(Market.SH)
     sz_count = c.get_security_count(Market.SZ)
     print(f"沪市证券总数: {sh_count}")
     print(f"深市证券总数: {sz_count}")
+
+# 运行结果:
+# 沪市证券总数: 2847
+# 深市证券总数: 3612