docs: add README with service overview and setup instructions

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

README.md

@@ -0,0 +1,79 @@
+# server-infra
+
+Shared Docker services for the Hetzner server: nginx proxy manager, umami analytics, Gitea + Actions runner.
+
+## Services
+
+| Service | Port (host) | Description |
+|---------|-------------|-------------|
+| nginx proxy manager | 80, 443, 81 (admin) | Reverse proxy + SSL termination |
+| umami | internal | Web analytics |
+| gitea | 127.0.0.1:3100 → nginx, 2222 (SSH) | Self-hosted git at `git.padelnomics.io` |
+| act_runner | — | Gitea Actions CI runner |
+
+## Directory layout
+
+```
+/opt/server-infra/          # this repo (owned by infra_service)
+├── gitea/docker-compose.yml
+├── reverse-proxy/docker-compose.yml   # recovered from running container
+├── umami/docker-compose.yml           # recovered from running container
+├── setup.sh                           # phase 1: user + dirs + uv
+└── bootstrap.sh                       # phase 2: recover compose files, start Gitea
+
+/data/server-infra/
+├── gitea/                  # Gitea data volume
+└── act_runner/             # Runner data volume
+```
+
+## Setup (new server)
+
+### Phase 1 — user, dirs, uv
+
+```bash
+ssh root@<server-ip> 'bash -s' < setup.sh
+```
+
+Creates `infra_service` system user (docker group), `/opt/server-infra/`, `/data/server-infra/`, installs uv.
+
+### Phase 2 — sync repo + recover
+
+```bash
+rsync -av --chown=infra_service:infra_service \
+    ~/Projects/server-infra/ root@<server-ip>:/opt/server-infra/
+
+ssh root@<server-ip> 'bash -s' < bootstrap.sh
+```
+
+Recovers `umami/docker-compose.yml` and `reverse-proxy/docker-compose.yml` from running containers, creates data dirs, sets ownership.
+
+### Phase 3 — start Gitea
+
+```bash
+ssh hetzner_root 'sudo -u infra_service docker compose \
+    -f /opt/server-infra/gitea/docker-compose.yml up -d'
+```
+
+Web installer at `http://<server-ip>:3100`. Set ROOT_URL to `https://git.padelnomics.io`.
+After setup, add a proxy host in nginx proxy manager → `127.0.0.1:3100`.
+
+### Phase 4 — start act_runner
+
+1. Generate a runner token in Gitea: Site Administration → Actions → Runners → Create runner token
+2. Create `/opt/server-infra/gitea/.env`:
+   ```
+   GITEA_RUNNER_TOKEN=<token>
+   ```
+3. Restart with the env file:
+   ```bash
+   ssh hetzner_root 'sudo -u infra_service docker compose \
+       -f /opt/server-infra/gitea/docker-compose.yml up -d'
+   ```
+
+## DNS
+
+`git.padelnomics.io` must be DNS-only (grey cloud) in Cloudflare — **not** proxied — so that SSH on port 2222 reaches the server directly.
+
+## Secrets
+
+The `infra_service` user owns all compose files. Secrets (runner token) go in `/opt/server-infra/gitea/.env` — never committed.