Initial scaffold: README, project layout, and headless-chromium render loop sketch

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+# InkyImpression
+
+Display server for a 13.3" Pimoroni Inky Impression on a Raspberry Pi Zero 2 W.
+
+## Hardware
+
+- **Display**: [Inky Impression 13.3"](https://shop.pimoroni.com/products/inky-impression) — 1600×1200, 6 colors (Spectra 6: red/green/blue/yellow/black/white), ~12s refresh (real-world 20–35s).
+- **Host**: Raspberry Pi Zero 2 W (quad-core ARMv7, 512 MB RAM — enough for headless Chromium on a single page).
+- **Buttons**: 4 tactile buttons on the back. For the 13.3" variant they map to BCM GPIO **5, 6, 25, 24** (note: 25, not 16 — see `reference/inky/examples/spectra6/buttons.py`).
+- **Mounting**: Pi Zero plugs straight into the socket header on the back. USB ports face down; text on Pi and Inky reads the same way up. **Power off before attaching/removing.**
+
+## What this project does
+
+Drives the Inky Impression to cycle through display "scenes":
+
+1. **Tasks** — pulled from the webapp tasks module (`~/dev/webapp/src/modules/tasks`).
+2. **Restaurant menu** — shown during the lunch window (12:00–13:00).
+3. **Announcements / events** — cycled via the 4 hardware buttons.
+
+## Architecture
+
+**Current strategy (this branch): headless Chromium on the Pi.**
+
+The webapp already renders the scenes we want (`tasks.ariege.io`, etc.), so the Pi runs `chromium --headless --screenshot` against the live URL, then pushes the PNG through PIL into the `inky` library. E-ink refresh is 20–35 s anyway, so a 5–15 s screenshot is comfortably within budget. Inky's `set_image()` handles dithering to the 6-color Spectra 6 palette.
+
+Other strategies we may try on branches later:
+
+- **Webapp JSON → PIL**: lighter, no browser, but layouts have to be redrawn by hand.
+- **External render service**: only worth it if multiple Pis share renders, or if Chromium-on-Pi proves too slow/flaky.
+
+## Initial Pi setup
+
+Flash **Raspberry Pi OS Bookworm or later** (the "with desktop" image is recommended by Pimoroni — pulls in the dependencies, but Lite works if you install them manually).
+
+On first boot:
+
+```bash
+sudo raspi-config
+# Interfacing Options → enable SPI and I2C
+sudo apt update && sudo apt upgrade -y
+sudo apt install -y git python3-venv python3-pip chromium-browser
+```
+
+Install the Inky library via Pimoroni's installer (creates `~/.virtualenvs/pimoroni`):
+
+```bash
+git clone https://github.com/pimoroni/inky
+cd inky
+./install.sh
+source ~/.virtualenvs/pimoroni/bin/activate
+```
+
+Verify the display is detected:
+
+```bash
+python3 -c "from inky.auto import auto; i = auto(verbose=True); print(i.resolution, i.colour)"
+```
+
+Quick smoke test using the bundled example:
+
+```bash
+cd ~/inky/examples/spectra6
+python3 image.py --file images/spectra6-1600x1200.png
+```
+
+Then clone this repo on the Pi and install into the same venv:
+
+```bash
+git clone <this-repo-url> ~/InkyImpression
+cd ~/InkyImpression
+pip install -e .
+inky-impression          # runs the main loop
+```
+
+## Project layout
+
+```
+.
+├── README.md
+├── pyproject.toml
+├── src/inky_impression/
+│   ├── __init__.py
+│   ├── __main__.py     # `python -m inky_impression`
+│   ├── main.py         # scheduler loop
+│   ├── render.py       # chromium screenshot → PIL → Inky
+│   └── scenes.py       # which URL to show at what time
+└── reference/inky/     # cloned Pimoroni library (gitignored)
+```
+
+## Reference
+
+- Pimoroni library (cloned for reference): `reference/inky/`
+  - `inky/inky_el133uf1.py` — driver for the 13.3" Spectra 6 panel
+  - `examples/spectra6/image.py` — minimal "draw an image" example
+  - `examples/spectra6/buttons.py` — button GPIO setup (remember: SW_C = 25 for 13.3")
+- [Pimoroni getting-started article](https://learn.pimoroni.com/article/getting-started-with-inky-impression)
+- Webapp tasks module: `~/dev/webapp/src/modules/tasks`
+
+## Version control
+
+This repo uses [jj](https://github.com/martinvonz/jj) (colocated with git):
+
+```bash
+jj st          # status
+jj describe    # set commit message for working copy
+jj new         # start a new change
+```