Update --only-failures help text to not reference --dots

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Co-Authored-By: Claude <noreply@anthropic.com>

Author: Claude Bot

src/cli/Arguments.zig

@@ -207,7 +207,7 @@ pub const test_only_params = [_]ParamType{
     clap.parseParam("--reporter <STR>                 Test output reporter format. Available: 'junit' (requires --reporter-outfile), 'dots'. Default: console output.") catch unreachable,
     clap.parseParam("--reporter-outfile <STR>         Output file path for the reporter format (required with --reporter).") catch unreachable,
     clap.parseParam("--dots                           Enable dots reporter. Shorthand for --reporter=dots.") catch unreachable,
-    clap.parseParam("--only-failures                  Only display test failures. Similar to --dots but without printing dots.") catch unreachable,
+    clap.parseParam("--only-failures                  Only display test failures, hiding passing tests.") catch unreachable,
     clap.parseParam("--max-concurrency <NUMBER>        Maximum number of concurrent tests to execute at once. Default is 20.") catch unreachable,
 };
 pub const test_params = test_only_params ++ runtime_params_ ++ transpiler_params_ ++ base_params_;