feat(auto-annotation): add LLM-based annotation operators

Add three new LLM-powered auto-annotation operators:
- LLMTextClassification: Text classification using LLM
- LLMNamedEntityRecognition: Named entity recognition with type validation
- LLMRelationExtraction: Relation extraction with entity and relation type validation

Key features:
- Load LLM config from t_model_config table via modelId parameter
- Lazy loading of LLM configuration on first execute()
- Result validation with whitelist checking for entity/relation types
- Fault-tolerant: returns empty results on LLM failure instead of throwing
- Fully compatible with existing Worker pipeline

Files added:
- runtime/ops/annotation/_llm_utils.py: Shared LLM utilities
- runtime/ops/annotation/llm_text_classification/: Text classification operator
- runtime/ops/annotation/llm_named_entity_recognition/: NER operator
- runtime/ops/annotation/llm_relation_extraction/: Relation extraction operator

Files modified:
- runtime/ops/annotation/__init__.py: Register 3 new operators
- runtime/python-executor/datamate/auto_annotation_worker.py: Add to Worker whitelist
- frontend/src/pages/DataAnnotation/OperatorCreate/hooks/useOperatorOperations.ts: Add to frontend whitelist

runtime/ops/annotation/llm_text_classification/process.py

@@ -0,0 +1,129 @@
+# -*- coding: utf-8 -*-
+"""LLM 文本分类算子。
+
+基于大语言模型对文本进行分类，输出分类标签、置信度和简短理由。
+支持通过 categories 参数自定义分类标签体系。
+"""
+
+import json
+import os
+import shutil
+import time
+from typing import Any, Dict
+
+from loguru import logger
+
+from datamate.core.base_op import Mapper
+
+
+SYSTEM_PROMPT = (
+    "你是一个专业的文本分类专家。根据给定的类别列表，对输入文本进行分类。\n"
+    "你必须严格输出 JSON 格式，不要输出任何其他内容。"
+)
+
+USER_PROMPT_TEMPLATE = """请对以下文本进行分类。
+
+可选类别：{categories}
+
+文本内容：
+{text}
+
+请以如下 JSON 格式输出（label 必须是可选类别之一，confidence 为 0~1 的浮点数）：
+{{"label": "类别名", "confidence": 0.95, "reasoning": "简短理由"}}"""
+
+
+class LLMTextClassification(Mapper):
+    """基于 LLM 的文本分类算子。"""
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self._model_id: str = kwargs.get("modelId", "")
+        self._categories: str = kwargs.get("categories", "正面,负面,中性")
+        self._output_dir: str = kwargs.get("outputDir", "") or ""
+        self._llm_config = None
+
+    def _get_llm_config(self) -> Dict[str, Any]:
+        if self._llm_config is None:
+            from ops.annotation._llm_utils import get_llm_config
+
+            self._llm_config = get_llm_config(self._model_id)
+        return self._llm_config
+
+    def execute(self, sample: Dict[str, Any]) -> Dict[str, Any]:
+        start = time.time()
+
+        text_path = sample.get(self.text_key)
+        if not text_path or not os.path.exists(str(text_path)):
+            logger.warning("Text file not found: {}", text_path)
+            return sample
+
+        text_path = str(text_path)
+        with open(text_path, "r", encoding="utf-8") as f:
+            text_content = f.read()
+
+        if not text_content.strip():
+            logger.warning("Empty text file: {}", text_path)
+            return sample
+
+        # 截断过长文本以适应 LLM 上下文窗口
+        max_chars = 8000
+        truncated = text_content[:max_chars]
+
+        from ops.annotation._llm_utils import call_llm, extract_json
+
+        config = self._get_llm_config()
+        prompt = USER_PROMPT_TEMPLATE.format(
+            categories=self._categories,
+            text=truncated,
+        )
+
+        try:
+            raw_response = call_llm(config, prompt, system_prompt=SYSTEM_PROMPT)
+            result = extract_json(raw_response)
+        except Exception as e:
+            logger.error("LLM classification failed for {}: {}", text_path, e)
+            result = {
+                "label": "unknown",
+                "confidence": 0.0,
+                "reasoning": f"LLM call or JSON parse failed: {e}",
+            }
+
+        annotation = {
+            "file": os.path.basename(text_path),
+            "task_type": "text_classification",
+            "categories": self._categories,
+            "model": config.get("model_name", ""),
+            "result": result,
+        }
+
+        # 确定输出目录
+        output_dir = self._output_dir or os.path.dirname(text_path)
+        annotations_dir = os.path.join(output_dir, "annotations")
+        data_dir = os.path.join(output_dir, "data")
+        os.makedirs(annotations_dir, exist_ok=True)
+        os.makedirs(data_dir, exist_ok=True)
+
+        base_name = os.path.splitext(os.path.basename(text_path))[0]
+
+        # 复制原始文本到 data 目录
+        dst_data = os.path.join(data_dir, os.path.basename(text_path))
+        if not os.path.exists(dst_data):
+            shutil.copy2(text_path, dst_data)
+
+        # 写入标注 JSON
+        json_path = os.path.join(annotations_dir, f"{base_name}.json")
+        with open(json_path, "w", encoding="utf-8") as f:
+            json.dump(annotation, f, indent=2, ensure_ascii=False)
+
+        sample["detection_count"] = 1
+        sample["annotations_file"] = json_path
+        sample["annotations"] = annotation
+
+        elapsed = time.time() - start
+        logger.info(
+            "TextClassification: {} -> {}, Time: {:.2f}s",
+            os.path.basename(text_path),
+            result.get("label", "N/A"),
+            elapsed,
+        )
+        return sample