feat(ack): shard task records for merge-safe workspaces

skills/ack/scripts/validate_tasks.py

@@ -25,13 +25,7 @@ import sys
 from pathlib import Path
 
 from approval_payload import approval_payload_hash
-from yaml_subset import (
-    DuplicateKeyError,
-    YamlSubsetError,
-    load_json_unique,
-    load_yaml_subset,
-    make_unique_pyyaml_loader,
-)
+from task_store import TaskStoreError, is_task_store_manifest, materialize_board, parse_document
 from worker_profiles import validate_orchestration
 from worker_profiles import validate_routing_document
 
@@ -243,38 +237,12 @@ def _nonempty_string(value: object) -> bool:
 
 def load_document(path: Path) -> dict:
     try:
-        content = path.read_text(encoding="utf-8")
-    except OSError as exc:
+        data = parse_document(path)
+        if is_task_store_manifest(data):
+            data = materialize_board(data, path)
+    except TaskStoreError as exc:
         sys.stderr.write(f"任务板读取失败: {exc}\n")
         raise SystemExit(1)
-
-    if path.suffix.lower() == ".json":
-        try:
-            data = load_json_unique(content)
-        except (json.JSONDecodeError, DuplicateKeyError) as exc:
-            sys.stderr.write(f"JSON 解析失败: {exc}\n")
-            raise SystemExit(1)
-    else:
-        try:
-            import yaml  # type: ignore
-        except ImportError:
-            try:
-                data = load_yaml_subset(content)
-            except YamlSubsetError as exc:
-                sys.stderr.write(f"YAML 子集解析失败: {exc}\n")
-                raise SystemExit(1)
-        else:
-            try:
-                data = yaml.load(
-                    content,
-                    Loader=make_unique_pyyaml_loader(yaml),
-                )
-            except yaml.YAMLError as exc:  # type: ignore
-                sys.stderr.write(f"YAML 解析失败: {exc}\n")
-                raise SystemExit(1)
-    if not isinstance(data, dict):
-        sys.stderr.write("任务板顶层必须是对象（mapping）\n")
-        raise SystemExit(1)
     return data
 
 
@@ -901,6 +869,11 @@ def validate_builtin(
     orchestration_override: dict | None = None,
 ) -> list[str]:
     errors: list[str] = []
+    store_errors = data.get("taskStoreErrors")
+    if isinstance(store_errors, list):
+        for error in store_errors:
+            if isinstance(error, str) and error.strip():
+                errors.append(f"taskStore: {error}")
     project_intake_workflow = "read-only-v1"
 
     def validate_string_fields(