fix(builder): harden extraction and vectorization edge cases (#685 #704 #718 #721 #737)

[simongu]

Summary

• 抽取的实体名写入图数据库时，id和name过滤掉了标点符号，希望保留这些标点符号话，应该在哪里修改代码 #737 Preserve punctuation in extracted entity names (was stripped to spaces by processing_phrases, e.g. 30cm/s → 30cm s). Added processing_phrases_preserve_punct and use it for stored entity name/id in the three SPG extractors; kept processing_phrases for matching/dedup keys.
• docker部署，在选择基于文本块和图谱混合索引管理器、或者基于表格索引管理器，向量化失败 #718 / 怎么解决啊 TypeError: 'NoneType' object is not iterable #747 BatchVectorizer crashed with TypeError: 'NoneType' object is not iterable when a vectorize model returned None for a batch. Added _coalesce_vectors to flatten safely and raise an actionable error; also fixed the async path feeding the unfiltered texts[start:end] instead of sub_texts.
• [Bug] [Module Name] KeyError: 'beforeText' #685 table_retriever threw KeyError: 'beforeText' because builder stores before_text/after_text (snake_case). Reads now tolerate both naming conventions.
• [Bug] [schema映射问题] Ner抽取Schema拼接问题 #704 medical_ner prompt used Chinese schema display names (extract_types → name_zh); now uses English type identifiers from load() (matching default_ner), so the LLM NER category aligns to SPG type identifiers.
• 按文档建外网知识库，搭建百度地图MCP，最后报抱歉，处理查询 今天深圳的天气 时发生异常。错误：'McpExecutor' object has no attribute 'kag_project_config', 请重试。 #721 Relocated the McpExecutor.schema() method that was accidentally defined at module level (referenced undefined self).

Files changed

• kag/common/utils.py
• kag/builder/component/extractor/schema_constraint_extractor.py
• kag/builder/component/extractor/schema_free_extractor.py
• kag/builder/component/extractor/knowledge_unit_extractor.py
• kag/builder/component/vectorizer/batch_vectorizer.py
• kag/builder/prompt/medical/ner.py
• kag/common/tools/algorithm_tool/chunk_retriever/table_retriever.py
• kag/solver/executor/mcp/mcp_executor.py

Test plan

• All changed files pass py_compile.
• pytest should be run in a configured env (import kag requires env setup).

Closes #737 #718 #747 #685 #704