Only count remote-unreachable commits as local work in finish guard

Why: 本地 main 停在 origin/main 顶端（克隆默认态）在 pin 为 feature 顶端时不在 pin
历史内，--branches 直判仍会误阻（本 worktree 自身收尾实测踩到）。
Evidence: 第五例回归（本地默认分支+克隆 reflog 不阻）全绿；五例套件+全套治理回归
GOVERNANCE-SUITE-OK；worktree 实际 finish 通过即端到端自证。
Impact: local_work_outside 候选提交先过 --not --remotes 过滤（远端可达即已保全）；
stash 仍恒算本地独有。

tests/test_task.py

@@ -758,6 +758,23 @@ class FinishGuardFixTests(unittest.TestCase):
         self.assertEqual(result.returncode, 0, result.stdout + result.stderr)
         self.assertFalse(wt.exists())
 
+
+    def test_local_default_branch_at_origin_main_does_not_block(self):
+        """克隆默认分支停在 origin/main 顶端（pin 为 feature 顶端时不在其历史内）
+        且 HEAD reflog 含克隆/检出轨迹——均为远端有副本的状态，不得阻断 finish。"""
+        self.add_submodule_pinned_off_main()
+        wt = self.worktree()
+        self.git(wt, "submodule", "update", "--init", "--recursive")
+        (self.repo / "tracked").write_text("implementation done\n")
+        self.git(self.repo, "add", "-A")
+        self.git(self.repo, "commit", "-q", "-m", "done")
+        self.git(self.repo, "push", "-q", "origin", "feature/guard")
+        self.git(self.repo, "merge", "--no-ff", "-q", "-m", "Merge feature/guard", "feature/guard")
+        self.git(self.repo, "push", "-q", "origin", "main")
+        result = self.task(wt, "finish", check=False)
+        self.assertEqual(result.returncode, 0, result.stdout + result.stderr)
+        self.assertFalse(wt.exists())
+
     def test_local_unique_commit_still_preserved(self):
         self.add_submodule_pinned_off_main()
         wt = self.worktree()