refactor(releaser): 将 manage-release 改名为 releaser

- skills/manage-release -> skills/releaser（git mv，内容不变）
- releaser 的 frontmatter/标题改名，description 保留旧名作为触发词
- skills/manage-release/ 保留为纯弃用占位（SKILL.md + README.md，指向 releaser），
  已装软链与旧项目 .pouch.yaml 不再悬空或失效
- 同步或引用：AGENTS.md、README.md、docs/getting-started.md、orc（routing/SKILL/README）、
  ack delivery、builder（SKILL/README/contract）、memory-distill、pouch onboard 与
  suggest_skills
- 测试：catalog 需列出旧名占位，新增弃用占位断言，orc children 纳入旧名占位

tests/test_orc_skill.py

@@ -44,11 +44,11 @@ class OrcSkillTests(unittest.TestCase):
         self.assertIn("当前 shell", skill)
         self.assertNotIn("用户未指定档位时采用以下判断", skill)
         self.assertNotIn("若该档位不足以安全完成", skill)
-        for child in ("$ack", "$manage-release", "$builder"):
+        for child in ("$ack", "$releaser", "$builder"):
             self.assertIn(child, routing)
 
     def test_children_do_not_reference_orc(self) -> None:
-        for child in ("ack", "manage-release", "builder"):
+        for child in ("ack", "releaser", "builder", "manage-release"):
             for path in (REPO_ROOT / "skills" / child).rglob("*"):
                 if not path.is_file() or "__pycache__" in path.parts:
                     continue