feat: add Gitea service (SQLite, HTTPS-only)

- gitea/docker-compose.yml: single container, SQLite, port 3000, data at
  /data/server-infra/gitea/
- setup.sh: restructure to separate recovery (one-time) from deploy (idempotent)
  for all services; add data dirs for gitea; loop over all services on deploy

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

gitea/docker-compose.yml

@@ -0,0 +1,14 @@
+services:
+  gitea:
+    image: gitea/gitea:latest
+    container_name: gitea
+    restart: always
+    ports:
+      - "3000:3000"
+    volumes:
+      - /data/server-infra/gitea:/data
+      - /etc/timezone:/etc/timezone:ro
+      - /etc/localtime:/etc/localtime:ro
+    environment:
+      - GITEA__database__DB_TYPE=sqlite3
+      - GITEA__server__SSH_DISABLED=true