feat(oa): add initiator system field to condition branches

Allow __initiator__ contains matching in publish validation and the
flow designer candidate list, excluding it from form useInCondition locks.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/services/oa_engine.py

@@ -1431,7 +1431,12 @@ def _eval_condition_rules(
         if op == "contains":
             if field == INITIATOR_CONDITION_FIELD:
                 uid = (initiator_user_id or "").strip()
-                allowed = {str(x or "").strip() for x in (val or [])}
+                if isinstance(val, list):
+                    allowed = {str(x or "").strip() for x in val if str(x or "").strip()}
+                elif isinstance(val, str) and val.strip():
+                    allowed = {val.strip()}
+                else:
+                    allowed = set()
                 if not uid or uid not in allowed:
                     return False
                 continue

backend/app/services/oa_publish.py

@@ -68,6 +68,9 @@ VALID_ASSIGNEE_TYPES = frozenset(
 
 VALID_NODE_TYPES = frozenset({"start", "approval", "cc", "condition", "end"})
 
+# 系统条件伪字段（非表单控件）
+INITIATOR_CONDITION_FIELD = "__initiator__"
+
 # 发布允许的控件 type（未知 type 拒绝）
 ALLOWED_CONTROL_TYPES = FILLABLE_TYPES | LAYOUT_TYPES
 
@@ -295,7 +298,7 @@ def validate_flow_tree(flow_tree: Any) -> List[str]:
 def validate_condition_rules_against_form(form_schema: Any, flow_tree: Any) -> List[str]:
     indexed = index_condition_fields(form_schema)
     errors: List[str] = []
-    seen: Set[str] = set()
+    seen_form: Set[str] = set()
 
     def collect_fields(node: Optional[Dict[str, Any]]) -> None:
         if not node or not isinstance(node, dict):
@@ -308,9 +311,21 @@ def validate_condition_rules_against_form(form_schema: Any, flow_tree: Any) -> L
                 if not isinstance(r, dict):
                     continue
                 field = (r.get("field") or "").strip()
-                if not field or field in seen:
+                if not field:
                     continue
-                seen.add(field)
+                if field == INITIATOR_CONDITION_FIELD:
+                    op = (r.get("op") or "").strip()
+                    val = r.get("value")
+                    if op != "contains":
+                        errors.append("发起人条件仅支持「包含」")
+                    elif not isinstance(val, list) or not any(
+                        str(x).strip() for x in val
+                    ):
+                        errors.append("发起人包含条件须选择至少一名用户")
+                    continue
+                if field in seen_form:
+                    continue
+                seen_form.add(field)
                 if field not in indexed:
                     errors.append(f"条件引用了无效字段：{field}")
             child = g.get("child")