Forum integration: Flarum extension, local test stack, embedded comments

- forum/extension: oc:import command (archived comments -> one thread per
  machine) and embed styling
- forum/docker: local Flarum 2 test stack
- site: optional params.forum.url adds a Forum menu entry and shows the
  machine thread in the Comments tab

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YDRjtmAiNpo5mK5N3d7QwZ

Makefile

@@ -7,10 +7,10 @@ PAGEFIND ?= npx -y pagefind@1
 DEPLOY_DIR ?= /run/user/$(shell id -u)/gvfs/smb-share:server=barbel-lescar,share=web/oldcomputers
 DEPLOY_URL ?= https://barbel.synology.me/oldcomputers/
 
-.PHONY: content build check serve deploy post
+.PHONY: content build check serve deploy post forum-up forum-import forum-down
 
 content:       ## regenerate content/ and static/media/ from the extraction repo
-	python3 $(OC)/scripts/05_hugo.py --target $(CURDIR)
+	python3 $(OC)/scripts/05_hugo.py --target $(CURDIR) $(if $(wildcard data/forum.json),--forum)
 
 build:         ## build the site and its search index into $(BUILD)/
 	rm -rf $(BUILD)
@@ -32,3 +32,17 @@ deploy: check  ## build, check, and copy $(BUILD)/ to DEPLOY_DIR (served at DEPL
 	mkdir -p "$(DEPLOY_DIR)"
 	rsync -r --size-only --info=stats1 $(BUILD)/media/ "$(DEPLOY_DIR)/media/"
 	rsync -rc --delete --exclude=/media/ --info=stats1 $(BUILD)/ "$(DEPLOY_DIR)/"
+
+# --- local test forum (Flarum in Docker, see forum/README.md) ---
+FORUM = docker compose -f forum/docker-compose.yml
+SITE_URL ?= http://localhost:1313
+
+forum-up:      ## start the test forum on http://localhost:8081 (admin / adminadmin)
+	$(FORUM) up -d --build
+
+forum-import:  ## export the archived comments and import them into the test forum
+	python3 $(OC)/scripts/06_forum.py --target $(CURDIR)
+	$(FORUM) exec -T flarum php flarum oc:import /import/machines.json --site-url=$(SITE_URL) --map=/import/forum.json
+
+forum-down:    ## stop the test forum (forum-db volume keeps its data)
+	$(FORUM) down