feat: 添加可配置场景注册表与规则引擎

- 新增场景基类、配置加载、注册表与原语模块
- 添加 r10_refund_split 规则及场景 JSON Schema
- 扩展 scan 引擎与 scenarios API
- 新增场景注册表/配置/集成测试
- 更新前端 App、api、labels 支持新场景

backend/app/engines/scan.py

@@ -15,6 +15,7 @@ from app.clues import service as clue_svc
 from app.clues.models import Clue
 from app.scenarios import churn_fraud as cf
 from app.scenarios import split_contract as sc
+from app.scenarios.base import BaseScenario
 
 MODEL_VERSION = "mock-llm@0.1"
 
@@ -98,3 +99,53 @@ def run_churn_scan(
             data_version_id=data_version_id,
         )
     return ScanResult("R9", len(retention_curve), clue)
+
+
+@dataclass
+class ScenarioRunResult:
+    """通用调度下单个场景的落库结果：扫描覆盖数 + 生成的线索列表。"""
+
+    scenario_code: str
+    scanned_count: int
+    clues: list[Clue]
+
+
+def run_scenarios(
+    session: Session,
+    scenarios: list[BaseScenario],
+    *,
+    data_version_id: uuid.UUID | None = None,
+    actor: str = "system",
+) -> list[ScenarioRunResult]:
+    """通用场景调度器：遍历已实例化的场景，检测→按阈值过滤→统一落库。
+
+    新增场景无需改动本函数：实现 BaseScenario 子类并经 @register_scenario 注册即可。
+    每个场景自报扫描覆盖数（证明全量性），超过阈值的草稿由本函数统一调 create_clue 落库。
+    """
+    results: list[ScenarioRunResult] = []
+    for scenario in scenarios:
+        outcome = scenario.scan(session, data_version_id=data_version_id)
+        created: list[Clue] = []
+        for draft in outcome.drafts:
+            if draft.score >= scenario.score_threshold:
+                created.append(
+                    clue_svc.create_clue(
+                        session,
+                        title=draft.title or scenario.title,
+                        risk_domain=scenario.risk_domain,
+                        scenario_code=scenario.code,
+                        score=draft.score,
+                        rationale=draft.rationale,
+                        evidence=draft.evidence,
+                        subjects=draft.subjects,
+                        amount_involved=draft.amount_involved,
+                        model_version=MODEL_VERSION,
+                        rule_version=scenario.rule_version,
+                        data_version_id=data_version_id,
+                        actor=actor,
+                    )
+                )
+        results.append(
+            ScenarioRunResult(scenario.code, outcome.scanned_count, created)
+        )
+    return results