Version-control the shared Caddy edge proxy

The droplet's single Caddy container terminates TLS for every site and routes
each host to its upstream over proxy_net. Until now its only copy lived on the
server; capture compose.yaml and the Caddyfile here, with a README covering how
to add a site and reload without downtime. ACME material is git-ignored.

.gitignore

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+# ACME material and issued certs - private keys, never commit.
+letsencrypt/
+acme.json
+
+# Caddy's data/config live in named Docker volumes on the droplet, not here.
+data/
+config/

Caddyfile

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+personaledson.com.br, app.personaledson.com.br, api.personaledson.com.br, www.personaledson.com.br {
+    reverse_proxy bigode-gateway-1:80
+}
+
+www.nazareonline.com.br, nazareonline.com.br {
+    reverse_proxy nazareonline-web-1:80
+}

README.md

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+# central-proxy
+
+The shared edge reverse proxy for the DigitalOcean droplet (`174.138.36.232`).
+A single **Caddy** container terminates TLS for every site on the box and routes
+each hostname to the right upstream container. It is the only thing published on
+ports 80 and 443; all the application stacks (bigode, nazareonline, ...) sit
+behind it on the external `proxy_net` Docker network and speak plain HTTP to it.
+
+Caddy manages Let's Encrypt certificates automatically - it obtains and renews a
+cert for each hostname listed in the `Caddyfile` on first request. Issued certs
+and ACME account keys persist in the `caddy_data` Docker volume (mounted at
+`/data`), not in this repo.
+
+## Layout
+
+```
+compose.yaml   the Caddy service: publishes 80/443, joins proxy_net,
+               bind-mounts the Caddyfile, persists certs in caddy_data
+Caddyfile      one site block per app; each reverse_proxies to a container
+               reachable by name on proxy_net
+```
+
+## Prerequisites
+
+- The external network exists: `docker network create proxy_net`.
+- Each upstream stack attaches its public-facing container to `proxy_net`, so
+  Caddy can reach it by container name (e.g. `nazareonline-web-1:80`).
+- DNS A records for every hostname in the `Caddyfile` point at the droplet.
+
+## Adding a site
+
+Add a block to the `Caddyfile` naming the hostname(s) and the upstream:
+
+```
+www.example.com, example.com {
+    reverse_proxy example-web-1:80
+}
+```
+
+The upstream container must be on `proxy_net`. Caddy forwards the original `Host`
+and sets `X-Forwarded-Proto: https`, so upstreams behind it can rebuild HTTPS
+URLs and do their own host canonicalisation.
+
+Then reload without downtime (does not disturb the other sites):
+
+```sh
+docker exec central-proxy-caddy-1 caddy reload --config /etc/caddy/Caddyfile
+```
+
+Validate a change before reloading:
+
+```sh
+docker run --rm -v "$PWD/Caddyfile":/etc/caddy/Caddyfile:ro caddy:2-alpine \
+  caddy validate --config /etc/caddy/Caddyfile
+```
+
+## Deploy
+
+The compose stack lives at `/home/waldson/central-proxy` on the droplet. To
+apply a change, copy the edited `Caddyfile` up and reload:
+
+```sh
+scp -i ~/.ssh/deploy_key ./Caddyfile waldson@174.138.36.232:/home/waldson/central-proxy/Caddyfile
+ssh -i ~/.ssh/deploy_key waldson@174.138.36.232 \
+  'docker exec central-proxy-caddy-1 caddy reload --config /etc/caddy/Caddyfile'
+```
+
+Bring the proxy up (or recreate it after a compose change) from that directory:
+
+```sh
+docker compose up -d
+```
+
+## Notes
+
+- `letsencrypt/acme.json` is leftover state from an earlier Traefik-based proxy
+  and is not used by Caddy. It is git-ignored (it contains private keys); it can
+  be deleted from the droplet once you are sure nothing references it.
+- Never `docker volume rm caddy_data` - that discards every issued certificate
+  and forces re-issuance, which can hit Let's Encrypt rate limits.

compose.yaml

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+name: central-proxy
+
+services:
+  caddy:
+    image: caddy:2-alpine
+    restart: unless-stopped
+    ports:
+      - "80:80"
+      - "443:443"
+    volumes:
+      - ./Caddyfile:/etc/caddy/Caddyfile
+      - caddy_data:/data
+      - caddy_config:/config
+    networks:
+      - proxy_net
+
+networks:
+  proxy_net:
+    external: true
+
+volumes:
+  caddy_data:
+  caddy_config: