feat: merge datetime fields in DataFrame output, hide MinuteBar internal fields

- K-line: daily+ periods output 'date' only, minute periods output 'datetime'
- Transactions (tick-by-tick): combine date param + hour/minute into 'datetime'
- XdxrRecord, HistoricalFundFlow: year/month/day merged to 'date'
- MinuteBar: rename unknown_1 to _unknown_1 (hidden from DataFrame)
- MinuteBar: add datetime column computed from bar index (A-share 240-bar pattern)
- get_minute_time_data: use history endpoint only (current-day endpoint broken in pytdx too)
- Update all examples to reflect new DataFrame column names

tests/unit/test_block_info.py

@@ -4,6 +4,8 @@ import asyncio
 import struct
 from unittest.mock import patch
 
+import pandas as pd
+
 from easy_tdx.client import AsyncTdxClient, TdxClient
 from easy_tdx.codec.block import parse_block_dat
 from easy_tdx.models.finance import TdxBlock
@@ -13,10 +15,11 @@ from easy_tdx.models.finance import TdxBlock
 def test_async_get_block_info_logic(mock_conn_cls):
     """测试 AsyncTdxClient.get_block_info 的异步拉取逻辑。"""
     mock_conn = mock_conn_cls.return_value
-    
+
     # 模拟异步 execute
     async def mock_execute(cmd):
         from easy_tdx.commands.block_info import GetBlockInfoCmd, GetBlockInfoMetaCmd
+
         if isinstance(cmd, GetBlockInfoMetaCmd):
             return 100, "hash"
         if isinstance(cmd, GetBlockInfoCmd):
@@ -32,9 +35,9 @@ def test_async_get_block_info_logic(mock_conn_cls):
         with patch("easy_tdx.client.parse_block_dat") as mock_parse:
             mock_parse.return_value = []
             res = await client.get_block_info("test.dat")
-            
-            assert isinstance(res, list)
-            assert mock_conn.execute.call_count == 2 # 1 meta + 1 data
+
+            assert isinstance(res, pd.DataFrame)
+            assert mock_conn.execute.call_count == 2  # 1 meta + 1 data
 
     asyncio.run(main())
 
@@ -49,20 +52,20 @@ def test_parse_block_dat_basic():
     # Header 384 + Count 2 + Record 2813
     data = bytearray(384)
     data.extend(struct.pack("<H", 1))  # 1 block
-    
+
     # Block Record: 9s (name) + H (count) + H (type) + 2800s (codes)
     name = "测试板块".encode("gbk")
     record = bytearray((name + b"\x00" * 9)[:9])
     record.extend(struct.pack("<HH", 2, 1))  # 2 stocks, type 1
-    
+
     # 2 stocks: 600000, 000001
     codes = "600000\x00000001\x00".encode("ascii")
     record.extend((codes + b"\x00" * 2800)[:2800])
-    
+
     data.extend(record)
-    
+
     blocks = parse_block_dat(bytes(data), "block_gn.dat")
-    
+
     assert len(blocks) == 1
     b = blocks[0]
     assert b.name == "测试板块"
@@ -75,12 +78,13 @@ def test_parse_block_dat_basic():
 def test_get_block_info_logic(mock_conn_cls):
     """测试 TdxClient.get_block_info 的分片拉取逻辑。"""
     mock_conn = mock_conn_cls.return_value
-    
+
     client = TdxClient("127.0.0.1")
-    
+
     # 模拟 GetBlockInfoMeta 响应：size=35000 (需要2次拉取)
     def mock_execute(cmd):
         from easy_tdx.commands.block_info import GetBlockInfoCmd, GetBlockInfoMetaCmd
+
         if isinstance(cmd, GetBlockInfoMetaCmd):
             return 35000, "dummy_hash"
         if isinstance(cmd, GetBlockInfoCmd):
@@ -89,16 +93,16 @@ def test_get_block_info_logic(mock_conn_cls):
         return None
 
     mock_conn.execute.side_effect = mock_execute
-    
+
     # 我们主要测试循环是否正确
     with patch("easy_tdx.client.parse_block_dat") as mock_parse:
         mock_parse.return_value = [TdxBlock("Test", 1, 0, [])]
         res = client.get_block_info("test.dat")
-        
+
         assert len(res) == 1
         # 应该调用了 1 (meta) + 2 (data: 30000 + 5000) = 3 次 execute
         assert mock_conn.execute.call_count == 3
-        
+
         # 验证最后一次拉取的参数
         last_call_args = mock_conn.execute.call_args_list[-1][0][0]
         assert last_call_args.start == 30000