cli/query_kanji: remove -k flag, use arguments

lib/cli/commands/query_kanji.dart

@@ -10,16 +10,11 @@ import 'package:args/command_runner.dart';
 class QueryKanji extends Command {
   final name = "query-kanji";
   final description = "Query the database for kanji data";
+  final invocation = "jadb query-kanji [options] <kanji>";
 
   QueryKanji() {
     addLibsqliteArg(argParser);
     addJadbArg(argParser);
-    argParser.addOption(
-      'kanji',
-      abbr: 'k',
-      help: 'The kanji to search for.',
-      valueHelp: 'KANJI',
-    );
   }
 
   Future<void> run() async {
@@ -34,10 +29,17 @@ class QueryKanji extends Command {
       libsqlitePath: argResults!.option('libsqlite')!,
     );
 
+    if (argResults!.rest.length != 1) {
+      print('You need to provide exactly one kanji character to search for.');
+      print('');
+      printUsage();
+      exit(64);
+    }
+
+    final String kanji = argResults!.rest.first.trim();
+
     final time = Stopwatch()..start();
-    final result = await JaDBConnection(db).jadbSearchKanji(
-      argResults!.option('kanji') ?? '漢',
-    );
+    final result = await JaDBConnection(db).jadbSearchKanji(kanji);
     time.stop();
 
     if (result == null) {