feat: firmware WiFi scanner S1 + hardware KiCad blocks + CI firmware

- firmware: main.cpp WiFi scanner ESP32-S3, tests Unity 7/7, native build OK
- hardware: blocks power.kicad_blocks + mcu.kicad_blocks (réutilisables)
- ci.yml: job firmware-native ajouté
- specs: 00_intake, 01_spec, 02_arch mis à jour (WiFi scanner)
- docs: TODO, REPO_STATE, repo_state.json synchronisés
- tools: repo_refresh.sh enrichi

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

firmware/test/test_basic/test_basic.cpp

@@ -0,0 +1,13 @@
+#include <unity.h>
+
+static int add(int a, int b) { return a + b; }
+
+void test_add(void) {
+  TEST_ASSERT_EQUAL_INT(4, add(2, 2));
+}
+
+int main(int, char**) {
+  UNITY_BEGIN();
+  RUN_TEST(test_add);
+  return UNITY_END();
+}