test(ui): Add comprehensive ParameterValidator test coverage

Expand test coverage for ParameterValidator with 500+ new test cases:

- Boundary value tests with floating-point precision checks
- Extreme value tests (double min/max, NaN, Infinity handling)
- Nested parameter validation (dot-path keys like "outer.inner.param")
- Deeply nested JSON structure validation
- Type safety tests (string, boolean, null, array, object rejection)
- Complex multi-constraint validation scenarios
- Integration tests with realistic model configurations
- Performance stress tests (100 parameters)
- Special floating-point values (subnormal, negative zero)

Tests verify validator correctly:
- Rejects non-finite numbers (NaN/Inf)
- Resolves nested paths via dot notation
- Provides detailed error messages with context
- Handles edge cases and malformed inputs

Motivation: Ensures robust parameter validation for physics simulations
and confirms dot-path nested key support works correctly.

Author: ahojukka5