test(cli): bare 'amy' exits 2; key generate rejects unknown flags

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CP4kfLCa3wWtE8Khy21Pkj

cli/src/main/kotlin/com/vitorpamplona/amethyst/cli/Main.kt

@@ -165,7 +165,7 @@ class AwaitTimeout(
 private val STRICT_ACCOUNT_VERBS = setOf("init", "create", "login", "logoff", "whoami")
 
 private suspend fun dispatch(argv: Array<String>): Int {
-    if (argv.isEmpty() || argv[0] == "--help" || argv[0] == "-h") {
+    if (argv.firstOrNull() == "--help" || argv.firstOrNull() == "-h") {
         printUsage()
         return 0
     }

cli/src/main/kotlin/com/vitorpamplona/amethyst/cli/commands/KeyCommands.kt

@@ -63,7 +63,7 @@ object KeyCommands {
             rest,
             "key <generate|public|encrypt|decrypt|validate>",
             mapOf(
-                "generate" to { _ -> generate() },
+                "generate" to { tail -> generate(tail) },
                 "public" to { tail -> public(tail) },
                 "encrypt" to { tail -> encrypt(tail) },
                 "decrypt" to { tail -> decrypt(tail) },
@@ -134,7 +134,8 @@ object KeyCommands {
         return 0
     }
 
-    private fun generate(): Int {
+    private fun generate(rest: Array<String>): Int {
+        Args(rest).rejectUnknown()
         val id = Identity.create()
         Output.emit(
             mapOf(