Add verified Joy-Con 2 USB bridge with native mouse support

Implement the standalone USB protocol probe and Bluetooth-backed right Joy-Con bridge with its own persistent virtual pairing identity. Preserve complete ordered native reports, including opaque motion data, and match the console feature set. Relay built-in vibration cues only after genuine source acknowledgement and expose safe BOOTSEL pairing control. Include native capture diagnostics and focused protocol, packet-lifecycle, and cue regressions. Native mouse operation confirmed on Switch with bridge 0.24; private captures and firmware backups remain outside the commit.

tests/test_switch2_mouse_bridge_native.py

@@ -0,0 +1,26 @@
+from pathlib import Path
+import shutil
+import subprocess
+
+
+def test_native_packet_fidelity_and_lifecycle(tmp_path: Path) -> None:
+    root = Path(__file__).resolve().parents[1]
+    cxx = shutil.which("c++") or shutil.which("g++")
+    assert cxx is not None, "a host C++ compiler is required"
+    probe = root / "tools" / "switch2_usb_probe"
+    executable = tmp_path / "switch2_mouse_bridge_test"
+    subprocess.run(
+        [cxx, "-std=c++17", "-Wall", "-Wextra", "-Werror", "-pthread",
+         "-DSWITCH_PICO_SWITCH2_USB_BRIDGE=1", "-DSWITCH_PICO_BLUEPAD32=1",
+         "-DSWITCH_PICO_ENABLE_BLE=1", "-DSWITCH_PICO_SWITCH2_MOUSE_CAPTURE=1",
+         "-DSWITCH_PICO_SWITCH2_MOUSE_CAPTURE_NATIVE=1",
+         "-DSWITCH2_BRIDGE_SOURCE_ADDRESS_BYTES=0x98,0xe2,0x55,0x07,0xdf,0x00",
+         f"-I{root / 'tests' / 'switch2_mouse_bridge_native_stubs'}",
+         f"-I{probe}", f"-I{root / 'src' / 'firmware'}", f"-I{root / 'bluepad32_config'}",
+         str(root / "tests" / "switch2_mouse_bridge_test.cpp"),
+         str(probe / "controller_input.cpp"),
+         str(root / "src" / "firmware" / "input" / "switch2_mouse_capture.cpp"),
+         "-o", str(executable)],
+        check=True, cwd=root,
+    )
+    subprocess.run([str(executable)], check=True, cwd=root)