fix: make command reconciliation binary safe

Assistant: codex
Assistant-Model: gpt-5.6-sol
Assistant-Session: 01a03397-4d51-7fd1-8ff2-946eb22ea2bc

tests/test_tmux_manager.py

@@ -184,6 +184,37 @@ def test_protocol_commands_absorb_forwarded_shell_lines(tmp_path):
         assert result.stdout == ""
 
 
+def test_protocol_reconciliation_skips_unrelated_binary_executables(tmp_path):
+    command_dir = tmp_path / "commands"
+    command_dir.mkdir()
+    binary = command_dir / "other-tool"
+    binary.write_bytes(b"\x7fELF\x8e\xff\x00")
+    legacy = command_dir / "@audit-core"
+    legacy.write_text(
+        "#!/bin/sh\n# tamq-address-command v1\nexit 0\n",
+        encoding="utf-8",
+    )
+    manager = tmux.TmuxManager("tamq-test", command_dir=command_dir)
+
+    manager._install_address_commands(["audit-core"])
+
+    assert binary.read_bytes() == b"\x7fELF\x8e\xff\x00"
+    assert not legacy.exists()
+    assert (command_dir / "To:audit-core:").is_file()
+
+
+def test_protocol_reconciliation_refuses_undecodable_command_collision(tmp_path):
+    command_dir = tmp_path / "commands"
+    command_dir.mkdir()
+    collision = command_dir / "To:audit-core:"
+    collision.write_bytes(b"\x8e\xff")
+    manager = tmux.TmuxManager("tamq-test", command_dir=command_dir)
+
+    with pytest.raises(tmux.TmuxError, match="cannot inspect existing command"):
+        manager._install_address_commands(["audit-core"])
+    assert collision.read_bytes() == b"\x8e\xff"
+
+
 def test_address_commands_reject_unsafe_repository_names(tmp_path):
     manager = tmux.TmuxManager("tamq-test", command_dir=tmp_path / "commands")
     with pytest.raises(tmux.TmuxError, match="cannot be exposed"):