Initial commit: Claude Usage Tracker for Panlee SC01 Plus

Physical desk monitor that displays Claude Code usage limits (5-hour session
and 7-day weekly utilization) on an ESP32-S3 touchscreen via USB serial.

Firmware: LVGL 9 dashboard with LovyanGFX on SC01 Plus, Anthropic brand
colors and custom fonts (Tiempos, Styrene B, DejaVu Sans Mono), Claude
spinner animation with rotating status words.

Daemon: Pure bash script that reads the Claude Code OAuth token, makes a
minimal Haiku API call, extracts usage from rate-limit response headers,
and sends JSON to the ESP32 over serial. Uses inotifywait for instant
USB plug/unplug detection.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

firmware/src/data.h

@@ -0,0 +1,12 @@
+#pragma once
+#include <Arduino.h>
+
+struct UsageData {
+    float session_pct;       // 5-hour window utilization (0-100)
+    int session_reset_mins;  // minutes until session resets
+    float weekly_pct;        // 7-day window utilization (0-100)
+    int weekly_reset_mins;   // minutes until weekly resets
+    char status[16];         // "allowed" or "limited"
+    bool ok;                 // data parse succeeded
+    bool valid;              // false until first successful parse
+};