fix: only infer target for wasm when GOOS and GOARCH are set correctly, not just based on file extension

Signed-off-by: deadprogram <ron@hybridgroup.com>

main.go

@@ -1684,8 +1684,24 @@ func main() {
 			usage(command)
 			os.Exit(1)
 		}
-		if options.Target == "" && filepath.Ext(outpath) == ".wasm" {
-			options.Target = "wasm"
+		if options.Target == "" {
+			switch {
+			case options.GOARCH == "wasm":
+				switch options.GOOS {
+				case "js":
+					options.Target = "wasm"
+				case "wasip1":
+					options.Target = "wasip1"
+				case "wasip2":
+					options.Target = "wasip2"
+				default:
+					fmt.Fprintln(os.Stderr, "GOARCH=wasm but GOOS is not set correctly. Please set GOOS to wasm, wasip1, or wasip2.")
+					os.Exit(1)
+				}
+			case filepath.Ext(outpath) == ".wasm":
+				fmt.Fprintln(os.Stderr, "you appear to want to build a wasm file, but have not specified either a target flag, or the GOARCH/GOOS to use.")
+				os.Exit(1)
+			}
 		}
 
 		err := Build(pkgName, outpath, options)