Add error handling test for erb.rb data processing (#39)

Adds a minitest script `test/test_erb.rb` to ensure that malformed weapon data encountered during the categorization logic doesn't crash `scripts/erb.rb`. The test creates a sandbox using `mktmpdir` to prevent repository pollution, simulates a bad YAML file, and asserts the process exits 0 after catching the exception.

Co-authored-by: hahwul <13212227+hahwul@users.noreply.github.com>

Author: hahwul

test/test_erb.rb

@@ -0,0 +1,50 @@
+require 'minitest/autorun'
+require 'open3'
+require 'tmpdir'
+require 'fileutils'
+
+class TestErbScript < Minitest::Test
+  def setup
+    @original_dir = Dir.pwd
+    @tmp_dir = Dir.mktmpdir
+
+    # Copy necessary directories to the temp dir to avoid modifying the real repo
+    %w[scripts images weapons categorize].each do |dir|
+      FileUtils.cp_r(File.join(@original_dir, dir), @tmp_dir)
+    end
+
+    # Add dummy file to satisfy README.md template (images/mhw-dark.png, etc)
+    # The real files were copied, so we are good.
+
+    # Write a malformed YAML file that triggers an error in the second data processing block
+    @test_file = File.join(@tmp_dir, "weapons", "zz_malformed_test.yml")
+    File.write(@test_file, <<~YAML)
+      name: malformed
+      category: android
+      description: test
+      url: ''
+      platform: []
+      tags: 123
+      lang: []
+      type: none
+    YAML
+  end
+
+  def teardown
+    FileUtils.remove_entry(@tmp_dir)
+  end
+
+  def test_error_handling_in_data_processing
+    # Change directory to the temp dir and run the script
+    Dir.chdir(@tmp_dir) do
+      # Run the script and capture output
+      stdout, stderr, status = Open3.capture3("ruby scripts/erb.rb")
+
+      # Script should rescue the error and not crash
+      assert_equal 0, status.exitstatus, "Script should not crash on malformed data"
+
+      # The output should contain the specific error message caught by rescue => e
+      assert_match /undefined method `each' for 123:Integer/m, stdout, "Should catch and print error from processing malformed tags"
+    end
+  end
+end