Initial commit: Paperwall, a standalone e-ink dashboard

Navidrome now-playing, clock, and weather for a Waveshare epd4in0e panel,
with a local web UI and install/uninstall scripts for the Pi.

paperwall.service.template

@@ -0,0 +1,16 @@
+[Unit]
+Description=Paperwall (Navidrome / Clock / Weather e-ink dashboard)
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=simple
+# Filled in by install.sh to point at this project's own self-contained venv.
+ExecStart={{PYTHON}} {{APP_DIR}}/main.py --host 0.0.0.0 --port 8080
+WorkingDirectory={{APP_DIR}}
+Restart=on-failure
+RestartSec=5
+User=root
+
+[Install]
+WantedBy=multi-user.target