container: remove global msg

This frees all container instances of side effects.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/app/app.go

@@ -6,23 +6,24 @@ import (
 	"log"
 	"os"
 
+	"hakurei.app/container"
 	"hakurei.app/hst"
 	"hakurei.app/internal/app/state"
 )
 
 // Main runs an app according to [hst.Config] and terminates. Main does not return.
-func Main(ctx context.Context, config *hst.Config) {
+func Main(ctx context.Context, msg container.Msg, config *hst.Config) {
 	var id state.ID
 	if err := state.NewAppID(&id); err != nil {
 		log.Fatal(err)
 	}
 
 	seal := outcome{id: &stringPair[state.ID]{id, id.String()}, syscallDispatcher: direct{}}
-	if err := seal.finalise(ctx, config); err != nil {
+	if err := seal.finalise(ctx, msg, config); err != nil {
 		printMessageError("cannot seal app:", err)
 		os.Exit(1)
 	}
 
-	seal.main()
+	seal.main(msg)
 	panic("unreachable")
 }