test: compile idle_state.h against Arduino's macro namespace

Companion to the HiveHub fix. These host tests build the pure headers
against a bare compiler, where Arduino's few hundred all-caps macros do not
exist — so a constant in the shared counter_protocol.h that collides with
one of them passes every check here and fails only in the firmware build.
HiveHub hit exactly that with an enumerator named DISABLED meeting
esp32-hal-gpio.h's `#define DISABLED 0x00`.

Define the macros that actually bite before the include, so the collision
surfaces in seconds on a host compiler instead of partway through a
firmware build.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016gFpezSuXW3sHMd1xaSYnd

Author: claude

Firmware/test/test_idle_state/test_idle_state.cpp

@@ -16,6 +16,30 @@
 // or via test/run_tests.sh, which builds every host test.
 // ============================================================================
 
+// ---------------------------------------------------------------------------
+// Arduino's macro soup, reproduced before the include on purpose.
+// ---------------------------------------------------------------------------
+// idle_state.h and counter_protocol.h are built two ways: here, against a bare
+// host compiler, and in the firmware, after Arduino.h has defined a few hundred
+// all-caps macros. The second is far more hostile, and a test that only sees
+// the first cannot catch a name collision — HiveHub hit exactly that, where an
+// enumerator named DISABLED met esp32-hal-gpio.h's `#define DISABLED 0x00` and
+// broke the build while every host check passed.
+//
+// So define the ones that actually bite, with their real Arduino values, before
+// the include. Any constant added to the shared protocol header that strays
+// into the all-caps macro namespace now fails on a host compiler in seconds
+// rather than partway through a firmware build. Deliberately NOT #undef'd.
+#define DISABLED 0x00
+#define INPUT 0x01
+#define OUTPUT 0x03
+#define PULLUP 0x04
+#define PULLDOWN 0x08
+#define HIGH 0x1
+#define LOW 0x0
+#define ANALOG 0xC0
+#define OPEN_DRAIN 0x10
+
 #include "idle_state.h"
 
 #include <cstdio>