fix: prevent browser target and focus surprises

- Respect the globally selected browser when renaming client aliases.
- Pass the resolved local profile into sync and async local transports so
  BROWSER_CLI_PROFILE is honored consistently.
- Stop tabs.active from explicitly focusing the OS browser window, avoiding
  virtual-desktop jumps during tab activation.
- Make window merging skip audible, unmuted windows so video playback windows
  are not selected as merge targets.
- Bump the Python package and extension manifest versions to 0.12.2.
- Add regression coverage for browser selection and focus-stealing behavior.

tests/test_cli.py

@@ -49,7 +49,7 @@ def test_clients_rename_uses_global_browser_target_when_set():
     result = CliRunner().invoke(main, ["--browser", "old-id", "clients", "rename", "work"])
 
   assert result.exit_code == 0
-  send_command.assert_called_once_with("clients.rename_profile", {"alias": "work"}, profile=None)
+  send_command.assert_called_once_with("clients.rename_profile", {"alias": "work"}, profile="old-id")
   assert "Restart the browser" not in result.output
 
 def test_clients_rename_rejects_duplicate_alias(tmp_path):
@@ -63,6 +63,16 @@ def test_clients_rename_rejects_duplicate_alias(tmp_path):
   assert "Browser alias 'work' already exists" in result.output
   send_command.assert_not_called()
 
+def test_clients_rename_duplicate_check_uses_global_browser_target(tmp_path):
+  registry_path = tmp_path / "registry.json"
+  registry_path.write_text('{"work": "/tmp/work.sock"}', encoding="utf-8")
+
+  with patch("browser_cli.commands.clients.REGISTRY_PATH", registry_path), patch("browser_cli.commands.clients.send_command") as send_command:
+    result = CliRunner().invoke(main, ["--browser", "work", "clients", "rename", "work"])
+
+  assert result.exit_code == 0
+  send_command.assert_called_once_with("clients.rename_profile", {"alias": "work"}, profile="work")
+
 def test_clients_rename_allows_same_alias_for_same_target(tmp_path):
   registry_path = tmp_path / "registry.json"
   registry_path.write_text('{"work": "/tmp/work.sock"}', encoding="utf-8")