feat(wasm): Add empty functions for js builds to enable WASM builds

signals_js.go

@@ -0,0 +1,9 @@
+//go:build js
+// +build js
+
+package tea
+
+// listenForResize is not available in js runtime.
+func (p *Program) listenForResize(done chan struct{}) {
+	close(done)
+}

tty_js.go

@@ -0,0 +1,21 @@
+//go:build js
+// +build js
+
+package tea
+
+import (
+	"errors"
+	"os"
+)
+
+func (p *Program) initInput() error {
+	return nil
+}
+
+func (p *Program) restoreInput() error {
+	return nil
+}
+
+func openInputTTY() (*os.File, error) {
+	return nil, errors.New("unavailable in js")
+}