Fix decimal separator format in calculator tool tests

[maeryo]

Changes

• Updated DecimalFormatSymbols to use period as decimal separator (Locale.US)
• Fixed test expectations in testComplexInputSchemaTool:
  • formattedResult: "11,000" → "11.000"
  • tags: Added actual test values ["test", "calculator", "integration"]
• Fixed test expectations in testComplexNestedSchema:
  • formattedResult: "0,00" → "0.00"

Motivation

1. Standard Decimal Notation: Using a comma as a decimal separator could be confusing as it's commonly used for thousands separators in many locales. Standardizing on the period (.) follows international conventions and makes the output clearer.

2. Test Data Correction: During the Validate PR workflow for Add metadata support to callTool method #289, discovered that the tags array in the expectedContent variable of testComplexInputSchemaTool() was incorrectly set to an empty array, which didn't match the actual input values being tested.