feat(cli): add admin REPL + commands and docs

- Add CLI entry in backend with default REPL, persistent history, aliases
- Add commands: users:list/create/verify, events:list/details/participants/checkin,
  matches:list, logs:app, logs:messages
- Support running subcommands inside REPL via .cli and run()
- Add Makefile targets: dev-cli, prod-cli, dev/prod up/down (+rebuild)
- Update README and add docs/ADMIN_CLI.md
- Add CLI tests with mocked Prisma

Makefile

@@ -0,0 +1,54 @@
+SHELL := /bin/bash
+COMPOSE ?= docker compose
+PROFILE ?= dev
+
+# Select backend service name based on profile
+ifeq ($(PROFILE),prod)
+BACKEND_SVC := backend-prod
+else
+BACKEND_SVC := backend
+endif
+
+.PHONY: help dev-cli prod-cli \
+        dev-up dev-down dev-up-rebuild \
+        prod-up prod-down prod-up-rebuild
+
+help:
+	@echo "Available targets:"
+	@echo "  make dev-cli                           # Start admin REPL in dev backend"
+	@echo "  make prod-cli                          # Start admin REPL in prod backend"
+	@echo "  make dev-up                            # docker compose --profile dev up"
+	@echo "  make dev-up-rebuild                    # docker compose --profile dev up --build"
+	@echo "  make dev-down                          # docker compose --profile dev down"
+	@echo "  make prod-up                           # docker compose --profile prod up -d"
+	@echo "  make prod-up-rebuild                   # docker compose --profile prod up -d --build"
+	@echo "  make prod-down                         # docker compose --profile prod down"
+	@echo "Notes: GNU Make nie wspiera subkomend z odstępami (np. 'make prod up')."
+	@echo "       Użyj odpowiednich celów z myślnikiem."
+
+# Admin CLI explicit targets
+dev-cli:
+	$(COMPOSE) exec backend npm run cli
+
+prod-cli:
+	$(COMPOSE) exec backend-prod npm run cli
+
+# Development profile
+dev-up:
+	$(COMPOSE) --profile dev up -d
+
+dev-up-rebuild:
+	$(COMPOSE) --profile dev up -d --build
+
+dev-down:
+	$(COMPOSE) --profile dev down
+
+# Production profile
+prod-up:
+	$(COMPOSE) --profile prod up -d
+
+prod-up-rebuild:
+	$(COMPOSE) --profile prod up -d --build
+
+prod-down:
+	$(COMPOSE) --profile prod down