app: remove split implementation

It is completely nonsensical and highly error-prone to have multiple implementations of this in the same build. This should be switched at compile time instead therefore the split packages are pointless.

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

internal/app/state/multi_test.go

@@ -0,0 +1,9 @@
+package state_test
+
+import (
+	"testing"
+
+	"hakurei.app/internal/app/state"
+)
+
+func TestMulti(t *testing.T) { testStore(t, state.NewMulti(t.TempDir())) }