build(go): add go-tw, set up go generate commands

Now, everything gets built with a single `go generate`!

go.mod

···
 module ladon
 
-go 1.23.7
+go 1.24.0
 
 toolchain go1.24.1
 
···
 )
 
 require (
+	github.com/Piszmog/go-tw v1.0.1 // indirect
 	github.com/a-h/parse v0.0.0-20250122154542-74294addb73e // indirect
 	github.com/andybalholm/brotli v1.1.0 // indirect
 	github.com/cenkalti/backoff/v4 v4.3.0 // indirect
···
 	golang.org/x/oauth2 v0.30.0 // indirect
 )
 
-tool github.com/a-h/templ/cmd/templ
+tool (
+	github.com/Piszmog/go-tw
+	github.com/a-h/templ/cmd/templ
+)

go.sum

···
+github.com/Piszmog/go-tw v1.0.1 h1:HL5ViJ6gqvp9vKWVgkAYnjJmvX8Y2sMBoUmkDPXk41U=
+github.com/Piszmog/go-tw v1.0.1/go.mod h1:mn9LjL3T9gMNAZ9XKU0rDmLunCbp/fetzAvWnOybRhw=
 github.com/a-h/parse v0.0.0-20250122154542-74294addb73e h1:HjVbSQHy+dnlS6C3XajZ69NYAb5jbGNfHanvm1+iYlo=
 github.com/a-h/parse v0.0.0-20250122154542-74294addb73e/go.mod h1:3mnrkvGpurZ4ZrTDbYU84xhwXW2TjTKShSwjRi2ihfQ=
 github.com/a-h/templ v0.3.833 h1:L/KOk/0VvVTBegtE0fp2RJQiBm7/52Zxv5fqlEHiQUU=

main.go

···
+//go:generate go tool templ generate
+//go:generate go tool go-tw -i tailwind.css -o static/styles.css
+
 package main
 
 import (