Migrate to Waveshare ESP32-S3-Touch-AMOLED-2.16 with auto-rotation, splash, and battery

Full hardware swap from Panlee SC01 Plus (480×320 IPS) to Waveshare 2.16"
square AMOLED (480×480, CO5300 + CST9220 + AXP2101 + QMI8658). Library
stack moves to Arduino_GFX, SensorLib, XPowersLib on the pioarduino
platform 55.03.38-1 (Arduino Core 3.x).

UI:
- 4 screens (splash, usage, controller, bluetooth) with 3-button physical
  navigation: GPIO 0 = prev, AXP PKEY = cycle, GPIO 18 = next.
- IMU-driven 90° auto-rotation. CO5300 can't rotate via MADCTL, so flush
  callback does CPU strip-rotation in PARTIAL render mode. Rotation
  transitions use AMOLED brightness flash (instant black → redraw → ramp).
- Battery indicator (Lucide icons) in upper-right, RGB565A8 alpha so it
  blends over the splash animations.
- USB plugged/unplugged auto-switches between Usage and Controller
  screens (suppressed while on splash).
- Fonts and icons re-scaled ~1.9× for the higher-DPI panel; 20px margins
  to clear rounded corners.

Splash:
- 13 × 20×20 pixel-art creature animations sourced from
  claudepix.vercel.app via tools/scrape_claudepix.js (scraper handles
  both PRESET creature-engine and standalone FRAMES+PAL formats).
  tools/convert_to_c.js emits firmware/src/splash_animations.h.
  Attribution preserved in README and the generated header.

Tooling:
- tools/png_to_lvgl.js converts alpha PNGs to LVGL RGB565A8 (planar
  layout, with --tint to colorize Lucide black-on-transparent sources).
- tools/scrape_claudepix.js, tools/convert_to_c.js for the splash
  pipeline.

Docs:
- New worktree CLAUDE.md with hardware pin map, file inventory, build
  commands, and the 8 critical gotchas (CO5300 rotation, OPI PSRAM,
  pioarduino requirement, LVGL 9 font patching, centralized touch read,
  even-aligned flush regions, touch swap/mirror values, RGB565A8 layout).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

tools/README.md

@@ -0,0 +1,53 @@
+# Splash animation tools
+
+Two-step pipeline for getting third-party 20×20 pixel animations onto the device.
+
+## 1. Scrape
+
+```bash
+node scrape_claudepix.js
+```
+
+Fetches the manifest from `claudepix.vercel.app/app.js`, then each animation's
+HTML file, evaluates the embedded JS in a Node VM context (loading the same
+`creature-engine.js` the site uses), and writes resolved frame data to
+`tools/claudepix_data/*.json`.
+
+Each output file looks like:
+```json
+{
+  "filename": "idle_breathe.html",
+  "name": "idle breathe",
+  "category": "Idle",
+  "description": "...",
+  "frame_count": 17,
+  "frames": [{ "hold": 500, "grid": [[0,0,...],[0,1,1,...],...] }, ...]
+}
+```
+
+Override URL or output dir with `--base` and `--out`.
+
+## 2. Convert to C
+
+```bash
+node convert_to_c.js
+```
+
+Reads `tools/claudepix_data/*.json` and emits a single
+`firmware/src/splash_animations.h` with:
+- `splash_<ident>_frames[N][400]` — per-frame cell codes (0 = empty, 1 = body, 2 = eye)
+- `splash_<ident>_holds[N]` — per-frame hold time in ms
+- `splash_anims[]` — master table with name, category, frame count, pointers
+- `SPLASH_ANIM_COUNT`
+
+The firmware (`splash.cpp`) consumes this header to render and animate.
+
+## Re-running
+
+The scraper is idempotent — re-run any time the source library updates. The
+converter overwrites the header. Rebuild firmware after running both.
+
+## License note
+
+The scraper hits a public site without a stated license. Confirm reuse is
+appropriate for your case before redistributing the output.