Move config file to ~/.config/fwd/config.toml

Presumably this also works for MacOS and windows.

While doing this, move away from xdg and home and use this
directories-next crate instead. Reverse connections still seem to
work.

Cargo.toml

@@ -18,8 +18,8 @@ anyhow = "1.0"
 bytes = "1"
 copypasta = "0.10.1"
 crossterm = { version = "0.28.1", features = ["event-stream"] }
+directories-next = "2"
 env_logger = { version = "0.11.5", default-features = false }
-home = "0.5.4"
 indoc = "1"
 log = { version = "0.4", features = ["std"] }
 open = "3"
@@ -29,7 +29,7 @@ thiserror = "1.0"
 tokio = { version = "1", features = ["io-std", "io-util", "macros", "net", "process", "rt", "rt-multi-thread", "fs"] }
 tokio-stream = "0.1"
 toml = "0.5"
-xdg = "2"
+
 
 [dev-dependencies]
 assert_matches = "1"