添加 Caddy Dockerfile，构建自定义 Caddy 镜像

caddy/Containerfile

@@ -0,0 +1,18 @@
+FROM docker.io/library/caddy:2-builder AS builder
+
+RUN xcaddy build \
+    --with github.com/caddyserver/nginx-adapter \
+    --with github.com/caddy-dns/cloudflare \
+    --with github.com/caddyserver/replace-response \
+    --with github.com/mholt/caddy-webdav \
+    --with github.com/mholt/caddy-ratelimit \
+    --with github.com/WeidiDeng/caddy-cloudflare-ip \
+    --with github.com/porech/caddy-maxmind-geolocation \
+    --with github.com/mholt/caddy-l4 \
+    --with github.com/aksdb/caddy-cgi/v2
+
+FROM docker.io/library/caddy:latest
+
+RUN apk update && apk add --no-cache git git-daemon cgit python3
+
+COPY --from=builder /usr/bin/caddy /usr/bin/caddy