Add Docker deployment config and v3.02 firmware docs

Deployment: Dockerfile (multi-stage dev/prod with Caddy static
serving), docker-compose.yml (caddy-docker-proxy labels),
Caddyfile, Makefile, .dockerignore.

Docs: v3.02 firmware page, v3.01 updates.

site/Makefile

@@ -0,0 +1,27 @@
+.PHONY: up down logs rebuild dev prod clean
+
+up:
+	docker compose up -d --build
+
+down:
+	docker compose down
+
+logs:
+	docker compose logs -f
+
+rebuild:
+	docker compose down
+	docker compose up -d --build
+
+dev:
+	@sed -i 's/^APP_ENV=.*/APP_ENV=dev/' .env
+	@sed -i 's/^APP_PORT=.*/APP_PORT=4321/' .env
+	$(MAKE) rebuild
+
+prod:
+	@sed -i 's/^APP_ENV=.*/APP_ENV=prod/' .env
+	@sed -i 's/^APP_PORT=.*/APP_PORT=80/' .env
+	$(MAKE) rebuild
+
+clean:
+	docker compose down --rmi local -v