refactor: deploy model — all files under /opt/pulse-lets-go

Single prefix deployment: /opt/pulse-lets-go/ contains
bin/, data/, web/, log/ — no more split across
/usr/local/bin, /etc, /usr/local/share, /var/log.

* Makefile: install → deploy target with PREFIX=/opt/pulse-lets-go
* deploy/pulse-lets-go.service: all paths under /opt/pulse-lets-go,
  removed stale nats.service dependency
* main.go: default dataDir = parent of exeDir (PREFIX/bin → PREFIX/data)
* README: updated all paths, step 1 uses make deploy

Makefile

@@ -1,12 +1,12 @@
 # pulse-lets-go — Telephone Load Balancer
 # Сборка Go backend + SvelteKit фронта в единый бинарник.
 
-APP     := pulse-lets-go
-BINDIR  := bin
+APP    := pulse-lets-go
+BINDIR := bin
 WEB_DIR := web
-DATA_DIR := data
+PREFIX := /opt/pulse-lets-go
 
-.PHONY: all build build-go build-web clean run test install \
+.PHONY: all build build-go build-web clean run test deploy \
         emulate emulate-normal emulate-overload emulate-cpu-low emulate-fail-high \
         emulate-node-down emulate-stale emulate-chaos build-emulator \
         build-siptest siptest-uas siptest-uac siptest-full
@@ -50,21 +50,23 @@ build-prod:
 	rm -rf $(BINDIR)/web && cp -r $(WEB_DIR)/build $(BINDIR)/web
 	CGO_ENABLED=0 go build -ldflags="-s -w" -o $(BINDIR)/$(APP) ./cmd/$(APP)
 
-# Установка: копирует бинарник и статику в /usr/local
-install: build
-	@echo "→ Установка в /usr/local"
-	mkdir -p /usr/local/share/$(APP)/web
-	cp -r $(WEB_DIR)/build /usr/local/share/$(APP)/web/
-	cp $(BINDIR)/$(APP) /usr/local/bin/$(APP)
-	chmod +x /usr/local/bin/$(APP)
-	@echo "✓ Установлен в /usr/local/bin/$(APP)"
+# Деплой в PREFIX: бинарник + статика + data + log
+deploy: build-prod
+	@echo "→ Деплой в $(PREFIX)"
+	install -d $(PREFIX)/bin $(PREFIX)/data $(PREFIX)/web $(PREFIX)/log
+	install -m 755 $(BINDIR)/$(APP) $(PREFIX)/bin/
+	cp -r $(WEB_DIR)/build/. $(PREFIX)/web/
+	@echo "✓ Готово: $(PREFIX)"
+	@echo "  $(PREFIX)/bin/$(APP)"
+	@echo "  $(PREFIX)/web/ (SvelteKit статика)"
+	@echo "  $(PREFIX)/data/ (config.json, trunks.json, users.json)"
+	@echo "  $(PREFIX)/log/ (ASCII-лог метрик)"
 
 # Установка systemd unit
 install-systemd:
-	@echo "→ Установка systemd unit"
-	cp deploy/$(APP).service /etc/systemd/system/
+	install -m 644 deploy/$(APP).service /etc/systemd/system/
 	systemctl daemon-reload
-	@echo "✓ systemd unit установлен. Запуск: systemctl start $(APP)"
+	@echo "✓ systemd unit установлен. Запуск: sudo systemctl start $(APP)"
 
 # ============================================================
 # Эмулятор метрик