Drop the external demo: the Widgets tab is the demo

The hamlab-demo site, its Widgets-tab button, the demo_url config key and the make publish
target that fed it are all gone, along with the public read-only token it needed. The
example stays in examples/external-demo as something to read. The installer one-liner
already comes from Gitea releases.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Makefile

@@ -2,7 +2,6 @@
 VERSION ?= $(shell git describe --tags --always 2>/dev/null || echo dev)
 GO      ?= go
 PREFIX  ?= /usr/local/bin
-PUBLISH ?= /home/core/apps/hamlab-demo/site
 
 # every architecture a release carries; arm is ARMv6 hard-float, so it covers every Raspberry Pi
 ARCHES  ?= amd64 arm64 arm 386 riscv64
@@ -10,7 +9,7 @@ LDFLAGS  = -s -w -X main.version=$(VERSION)
 # static, no cgo: the same file runs on glibc, musl (Alpine) and anything else with a Linux kernel
 GOBUILD  = CGO_ENABLED=0 GOOS=linux GOARM=6 $(GO) build -trimpath -ldflags "$(LDFLAGS)"
 
-.PHONY: all web build go dev cross release publish gitea-release deploy push-nodes push-nodes-force test clean
+.PHONY: all web build go dev cross release gitea-release deploy push-nodes push-nodes-force test clean
 
 all: build
 
@@ -61,9 +60,7 @@ gitea-release: release
 deploy: build cross
 	./bin/hamlab install --prefix $(PREFIX)
 	@sleep 1; $(PREFIX)/hamlab push-nodes || true
-	@# The public installer must never lag the fleet: it would offer everyone an older build, and
-	@# "upgrade" a current machine backwards. Publish only where this hub serves the download site.
-	@if [ -d $(PUBLISH) ]; then $(MAKE) --no-print-directory publish; fi
+	@echo "deployed $(VERSION); 'make gitea-release' publishes it for everyone else"
 
 # push the installed binary to every managed machine (what deploy does last)
 push-nodes:
@@ -75,13 +72,3 @@ push-nodes-force:
 
 clean:
 	rm -rf bin dist internal/web/dist web/dist
-
-# Put the release where `curl -fsSL https://hamlab-demo.bigham.dev/install.sh | sh` finds it:
-# the static site beside the demo page (nginx, public through NPM). Binaries first, VERSION
-# last, so nobody is ever pointed at files that aren't there yet.
-publish: release
-	mkdir -p $(PUBLISH)/dl
-	cp dist/hamlab-linux-* dist/SHA256SUMS $(PUBLISH)/dl/
-	cp dist/install.sh $(PUBLISH)/dl/install.sh && cp dist/install.sh $(PUBLISH)/install.sh
-	cp dist/VERSION $(PUBLISH)/dl/VERSION
-	@echo "published $(VERSION): curl -fsSL https://hamlab-demo.bigham.dev/install.sh | sh"