chore: improve lpa string parsing

app-common/src/main/java/im/angry/openeuicc/util/LPAString.kt

@@ -9,11 +9,12 @@ data class LPAString(
     companion object {
         fun parse(input: String): LPAString {
             var token = input
-            if (token.startsWith("LPA:", ignoreCase = true)) token = token.drop(4)
+            if (token.startsWith("LPA:", true)) token = token.drop(4)
             val components = token.split('$').map { it.trim().ifBlank { null } }
-            check(components.getOrNull(0) == "1") { "Invalid AC_Format" }
+            check(components.size > 1) { "Invalid activation code format" }
+            check(components[0] == "1") { "Invalid AC_Format" }
             return LPAString(
-                checkNotNull(components.getOrNull(1)) { "SM-DP+ is required" },
+                checkNotNull(components[1]) { "SM-DP+ is required" },
                 components.getOrNull(2),
                 components.getOrNull(3),
                 components.getOrNull(4) == "1"