Enable firmware tests

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

tests/firmware/CMakeLists.txt

@@ -0,0 +1,24 @@
+cmake_minimum_required(VERSION 3.13)
+
+project(switch-pico-firmware-tests LANGUAGES CXX)
+
+enable_testing()
+
+add_executable(switch-pico-firmware-tests
+    ../../switch2_commands.cpp
+    ../../switch2_descriptors.cpp
+    ../../switch2_reports.cpp
+    ../../switch_uart_protocol.cpp
+    test_main.cpp
+    test_legacy_descriptors.cpp
+    test_switch2_commands.cpp
+    test_switch2_descriptors.cpp
+    test_switch2_reports.cpp
+    test_switch_input.cpp
+    test_switch_uart_protocol.cpp
+)
+
+target_compile_features(switch-pico-firmware-tests PRIVATE cxx_std_17)
+target_include_directories(switch-pico-firmware-tests PRIVATE ../..)
+
+add_test(NAME switch-pico-firmware-tests COMMAND switch-pico-firmware-tests)

tests/firmware/test_main.cpp

@@ -0,0 +1,12 @@
+#include "test_support.h"
+
+int main() {
+    TestRunner runner;
+    run_legacy_descriptor_tests(runner);
+    run_switch2_command_tests(runner);
+    run_switch2_descriptor_tests(runner);
+    run_switch2_report_tests(runner);
+    run_switch_input_tests(runner);
+    run_switch_uart_protocol_tests(runner);
+    return runner.result();
+}