feat: project scaffolding with PlatformIO config and boot skeleton

Co-authored-by: Cursor <cursoragent@cursor.com>

src/main.cpp

@@ -0,0 +1,26 @@
+#include <Arduino.h>
+#include <M5Unified.h>
+#include "config.h"
+
+void setup() {
+    auto cfg = M5.config();
+    M5.begin(cfg);
+
+    Serial.begin(115200);
+    Serial.println("[main] Immich Frame booting...");
+
+    // Disable audio permanently
+    pinMode(PIN_AUDIO_PWR_EN, OUTPUT);
+    digitalWrite(PIN_AUDIO_PWR_EN, LOW);
+    pinMode(PIN_SPK_EN, OUTPUT);
+    digitalWrite(PIN_SPK_EN, LOW);
+
+    Serial.printf("[main] Free heap: %d, PSRAM: %d\n",
+                  ESP.getFreeHeap(), ESP.getFreePsram());
+    Serial.println("[main] Boot complete (skeleton)");
+}
+
+void loop() {
+    M5.update();
+    delay(1000);
+}