feat(nix): nix and back again

I tried Nix, but it had too many downsides so I removed it.

1. Didn't like that all files are immutable and simple config changes
need a complete rebuild.
2. Setting up a new Mac didn't work as smoothly as promised. Not worth
the effort.
3. It sucked a lot to always have to type in the password twice on each
darwin-rebuild
4. It solves problems I never had.

.functions/server.sh

@@ -0,0 +1,11 @@
+# Server
+
+server() {
+    if command -v browser-sync >/dev/null 2>&1; then
+        echo "Starting Browser-Sync server..."
+        browser-sync start --server --files "${1:-**}" "${@:2}"
+    else
+        echo "Error: browser-sync is not installed or not in the PATH."
+        echo "Please install it using npm: npm install -g browser-sync"
+    fi
+}