feat: sdk migration in progress

internal/keys/base64util.go

@@ -0,0 +1,35 @@
+package keys
+
+import (
+	"encoding/base64"
+	"errors"
+	"strings"
+)
+
+func decode32ByteKey(s string) ([]byte, error) {
+	try := func(enc *base64.Encoding, v string) ([]byte, bool) {
+		if b, err := enc.DecodeString(v); err == nil && len(b) == 32 {
+			return b, true
+		}
+		return nil, false
+	}
+
+	// Try raw (no padding) variants first
+	if b, ok := try(base64.RawURLEncoding, s); ok {
+		return b, nil
+	}
+	if b, ok := try(base64.RawStdEncoding, s); ok {
+		return b, nil
+	}
+
+	// Try padded variants (add padding if missing)
+	pad := func(v string) string { return v + strings.Repeat("=", (4-len(v)%4)%4) }
+	if b, ok := try(base64.URLEncoding, pad(s)); ok {
+		return b, nil
+	}
+	if b, ok := try(base64.StdEncoding, pad(s)); ok {
+		return b, nil
+	}
+
+	return nil, errors.New("key must be 32 bytes in base64/base64url")
+}