docs: write operator README

Repo had a 0-byte README. New one covers:
- Single-service inventory with the load-bearing cloudflared-mcp
  container name (vault-mcp's legacy network aliases depend on it)
- Token-mode + dashboard-managed ingress contract
- .env contract (TUNNEL_TOKEN)
- Token rotation flow + how to map a new public hostname
- Cross-reference to homelab-ansible's roles/cloudflared README for
  the redirect-loop gotcha on Traefik backends
- No-ports / one-tunnel / :latest gotchas

Working tree has an in-flight docker-compose.yml → compose.yml rename
(D docker-compose.yml + ?? compose.yml). Intentionally not part of
this commit.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

README.md

@@ -0,0 +1,74 @@
+# cloudflared
+
+Token-mode Cloudflare tunnel that fronts the homelab's MCP services and
+admin UIs. Outbound-only from the host — no inbound ports.
+
+Routes `*.herbylab.dev` hostnames (e.g. `vault.herbylab.dev`,
+`auth.herbylab.dev`, `trellis.herbylab.dev`) to in-network services on
+the shared `homelab` Docker network. **Ingress rules live in the
+Cloudflare Zero Trust dashboard**, not in this repo.
+
+## Service
+
+| Service       | Image                            | Container name      |
+|---------------|----------------------------------|---------------------|
+| `cloudflared` | `cloudflare/cloudflared:latest`  | `cloudflared-mcp`   |
+
+The `cloudflared-mcp` container name is **load-bearing**: it's the same
+hostname the legacy network aliases on `vault-mcp` (`homelab-mcp`,
+`herbydev-mcp`) expect, so renaming the container breaks dashboard
+ingress until the tunnel config is repointed.
+
+## Run it
+
+```bash
+docker compose up -d
+docker compose logs -f cloudflared
+```
+
+## Configuration
+
+| File           | Purpose                                                 |
+|----------------|---------------------------------------------------------|
+| `compose.yml`  | Single-service definition + external `homelab` network  |
+| `.env`         | `TUNNEL_TOKEN` (from Cloudflare Zero Trust dashboard) — gitignored |
+
+To create / rotate the tunnel:
+
+1. Cloudflare Zero Trust dashboard → Networks → Tunnels.
+2. Create a new tunnel (or rotate the token on the existing one).
+3. Paste the connector token into `.env` as `TUNNEL_TOKEN=...`.
+4. Restart: `docker compose up -d`.
+
+To map a new public hostname to a backend:
+
+1. Cloudflare dashboard → tunnel → Public Hostnames → Add a public
+   hostname.
+2. Origin = `http://<container>:<port>` (the backend must be on the
+   `homelab` Docker network so this `cloudflared-mcp` container can
+   reach it by service name).
+3. No restart needed — the connector reloads dashboard config on its own.
+
+For HTTPS-only backends (Traefik et al.), use
+`https://<container>:443` with "No TLS Verify" — see the
+`roles/cloudflared` README in `homelab-ansible` for the redirect-loop
+gotcha when targeting `:80`.
+
+## Gotchas
+
+- **Token-mode = no `ports:` block.** This is outbound-only by
+  construction. If you find yourself adding a `ports:` entry, you're
+  misconfiguring — backends are reached *outbound* from the connector,
+  not inbound.
+- **External `homelab` network must exist** before this stack starts.
+  Backends must also be on the `homelab` network (or a network shared
+  with it) for `cloudflared-mcp` to resolve them by container name.
+- **One container, one tunnel.** Multiple tunnels = multiple compose
+  stacks (or a parameterized invocation pattern — see the
+  `roles/cloudflared` Ansible role in `homelab-ansible` for that
+  approach).
+- **`:latest` image tag.** No pinning. If a connector upgrade breaks
+  ingress, pin to the last-known-good tag and re-deploy.
+- The repo also contains some leftover uv-init artifacts (`main.py`,
+  `pyproject.toml`, `uv.lock`, `.python-version`). These are not part
+  of the deployment.