docs: update default difficulty to 4

Signed-off-by: Xe Iaso <me@xeiaso.net>

docs/docs/admin/environments/docker-compose.mdx

@@ -8,7 +8,7 @@ services:
     image: ghcr.io/techarohq/anubis:latest
     environment:
       BIND: ":8080"
-      DIFFICULTY: "5"
+      DIFFICULTY: "4"
       METRICS_BIND: ":9090"
       SERVE_ROBOTS_TXT: "true"
       TARGET: "http://nginx"

docs/docs/admin/installation.mdx

@@ -55,7 +55,7 @@ Anubis uses these environment variables for configuration:
 | `BIND_NETWORK`                 | `tcp`                   | The address family that Anubis listens on. Accepts `tcp`, `unix` and anything Go's [`net.Listen`](https://pkg.go.dev/net#Listen) supports.                                                                                                                                               |
 | `COOKIE_DOMAIN`                | unset                   | The domain the Anubis challenge pass cookie should be set to. This should be set to the domain you bought from your registrar (EG: `techaro.lol` if your webapp is running on `anubis.techaro.lol`). See [here](https://stackoverflow.com/a/1063760) for more information.               |
 | `COOKIE_PARTITIONED`           | `false`                 | If set to `true`, enables the [partitioned (CHIPS) flag](https://developers.google.com/privacy-sandbox/cookies/chips), meaning that Anubis inside an iframe has a different set of cookies than the domain hosting the iframe.                                                           |
-| `DIFFICULTY`                   | `5`                     | The difficulty of the challenge, or the number of leading zeroes that must be in successful responses.                                                                                                                                                                                   |
+| `DIFFICULTY`                   | `4`                     | The difficulty of the challenge, or the number of leading zeroes that must be in successful responses.                                                                                                                                                                                   |
 | `ED25519_PRIVATE_KEY_HEX`      | unset                   | The hex-encoded ed25519 private key used to sign Anubis responses. If this is not set, Anubis will generate one for you. This should be exactly 64 characters long. See below for details.                                                                                               |
 | `ED25519_PRIVATE_KEY_HEX_FILE` | unset                   | Path to a file containing the hex-encoded ed25519 private key. Only one of this or its sister option may be set.                                                                                                                                                                         |
 | `METRICS_BIND`                 | `:9090`                 | The network address that Anubis serves Prometheus metrics on. See `BIND` for more information.                                                                                                                                                                                           |

docs/docs/funding.md

@@ -7,4 +7,4 @@ Anubis is provided to the public for free in order to help advance the common go
 
 If you want to run an unbranded or white-label version of Anubis, please [contact Xe](https://xeiaso.net/contact) to arrange a contract. This is not meant to be "contact us" pricing, I am still evaluating the market for this solution and figuring out what makes sense.
 
-You can donate to the project [on Patreon](https://patreon.com/cadey).
+You can donate to the project [on Patreon](https://patreon.com/cadey) or via [GitHub Sponsors](https://github.com/sponsors/Xe).