feat: flesh out strategies + server + config

[alecthomas]

This implements a "direct host" strategy, and a "default" strategy that replaces the remote server component.

eg.

Server

~/dev/sfptc $ cat sfptc.hcl
# strategy git {}
# strategy docker {}
# strategy hermit {}
# strategy artifactory {
#   mitm = ["artifactory.global.square"]
# }

host "/github/" {
  target = "https://github.com/"
}

disk {
  root = "./cache"
}

~/dev/sfptc $ sfptcd --config=sfptc.hcl --log-level=debug
DBG Cache backend cache=disk:/Users/alec/dev/sfptc/cache
DBG Adding strategy strategy=default pattern=/api/v1/
DBG Adding strategy strategy=host:github.com/ pattern=/github/
INF Starting sfptcd bind=127.0.0.1:8080

Client:

~/dev/sfptc $ curl http://127.0.0.1:8080/github/foo | wc                    aat/server-and-strategy
~/dev/sfptc $ curl -H 'Time-To-Live: 1h' --data-binary 'Hello world' -i http://127.0.0.1:8080/api/v1/01ba4719c80b6fe911b091a7c05124b64eeece964e09c058ef8f9805daca546b
HTTP/1.1 200 OK
Date: Wed, 07 Jan 2026 03:04:47 GMT
Content-Length: 0

~/dev/sfptc $ curl -i http://127.0.0.1:8080/api/v1/01ba4719c80b6fe911b091a7c05124b64eeece964e09c058ef8f9805daca546b
HTTP/1.1 200 OK
Date: Wed, 07 Jan 2026 03:05:24 GMT
Content-Length: 11
Content-Type: text/plain; charset=utf-8

Hello world