Rename package from @valknar/vpinball-wasm to vpinball-wasm

Unscoped, matching this project's other Gitea-published package
(triggershell) - the registry is already scoped to the right owner via
publishConfig.registry's URL path (.../valknar/npm/), so an npm scope
on the package name itself is redundant. The old @valknar/vpinball-wasm
package published under the previous name is being removed manually.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

package.json

@@ -1,5 +1,5 @@
 {
-	"name": "@valknar/vpinball-wasm",
+	"name": "vpinball-wasm",
 	"version": "0.1.0",
 	"description": "Visual Pinball's engine compiled to WebAssembly - real .vpx tables, real VBScript, WebGL2 rendering, in the browser",
 	"license": "SEE LICENSE IN LICENSE",