chore: delete backend

Initially, the backend was meant to cache calls to the GitHub API.
However, I decided to just cache them in the sessionStorage of the
visitor’s browser instead.

Cargo.toml

@@ -1,21 +0,0 @@
-[package]
-name = "phuncache"
-version = "0.1.0"
-edition = "2021"
-authors = ["Lucien Cartier-Tilet <lucien@phundrak.com>"]
-homepage = "https://labs.phundrak.com/phundrak/phundrak.com"
-license = "AGPL-3.0"
-publish = false
-
-[dependencies]
-actix-web = "4"
-env_logger = "0.10.0"
-derive_more = "0.99.17"
-serde = { version = "1.0", features = ["derive"] }
-dotenvy = "0.15"
-gql_client = "1.0.7"
-human-panic = "1.1.0"
-
-[[bin]]
-name = "phuncache"
-path = "src/main.rs"