Add Numeric Comparison Assertions And Dashboard Preview Polish

[javaChip56]

Summary

• add support for numeric comparison assertions: greaterThan, greaterThanOrEqual, lessThan, and lessThanOrEqual
• expose the new numeric rules in the cURL importer assertion builder for numeric response fields
• improve response preview readability in both the cURL importer and dashboard test results with JSON formatting and wrap toggles
• increase selection tree contrast so group headers and child test rows are easier to distinguish
• add the cURL-style accent edge treatment to the Test selection and Test results cards

Details

• extended the core assertion model and evaluator to handle numeric comparisons cleanly
• wired assertion token/value resolution through the execution path for the new rules
• added evaluator test coverage for successful numeric comparisons and non-numeric failure handling
• updated README documentation for the new assertion keywords and token support
• polished the UI so long JSON payloads are easier to inspect during test authoring and result review

Verification

• dotnet build ApiTestRunner.sln -c Release
• dotnet test ApiTestRunner.sln -c Release --no-build

[javaChip56]

Ok to merge.

[javaChip56]

Ok to merge.