chore: contributor workflow — templates, git-cliff, gitea-workflow doc (closes #31) (#38)

Makefile

@@ -19,7 +19,7 @@ export DOCKER_HOST := unix://$(PODMAN_SOCK)
 endif
 endif
 
-.PHONY: ci lint build unit smoke down help
+.PHONY: ci lint build unit smoke down changelog help
 
 ## ci: run the full pipeline — lint, build, unit, smoke (mirrors Gitea Actions)
 ci: lint build unit smoke
@@ -45,6 +45,10 @@ smoke:
 down:
 	docker compose -f $(COMPOSE) down --volumes
 
+## changelog: regenerate CHANGELOG.md from Conventional Commits (git-cliff)
+changelog:
+	git-cliff --output CHANGELOG.md
+
 ## help: list available targets
 help:
 	@grep -E '^## ' $(MAKEFILE_LIST) | sed 's/^## //'