Remove deprecated test files and optimize encryption functions

- Deleted `testresults.txt` and `testmain_test.go` as they were no longer needed.
- Updated the Go workflow to streamline the build process by removing commented-out build steps for various platforms.
- Refactored encryption benchmarks to improve performance and clarity in the `benchmark_test.go` file.
- Introduced a new LICENSE file for the encryption package, specifying the MIT License.
- Enhanced the README with usage instructions and links to the NIP-44 specification.
- Bumped version to v0.25.3 to reflect these changes.

pkg/protocol/nwc/uri.go

@@ -75,8 +75,8 @@ func ParseConnectionURI(nwcUri string) (parts *ConnectionParams, err error) {
 		return
 	}
 	parts.clientSecretKey = clientKey
-	if parts.conversationKey, err = encryption.GenerateConversationKeyWithSigner(
-		clientKey,
+	if parts.conversationKey, err = encryption.GenerateConversationKey(
+		clientKey.Sec(),
 		parts.walletPublicKey,
 	); chk.E(err) {
 		return