[Swift6] Fix incorrect ParameterConvertible conformance for number enums

[berk-dilek]

Potentially fixes - #22624
When a property has 'type: number' without an explicit format, the generated enum incorrectly conformed to ParameterConvertible. This caused compilation errors because the enum already gets the asParameter method via the RawRepresentable extension in Extensions.swift.

The issue occurred because the template only checked isDouble (which requires 'format: double') but not isNumeric (which is set for all number types).

Added {{^isNumeric}} check to prevent ParameterConvertible conformance for all numeric enum types, not just those with explicit format.

Affected templates:

• modelEnum.mustache
• modelInlineEnumDeclaration.mustache

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Summary by cubic

Prevent incorrect ParameterConvertible conformance for Swift 6 numeric enums, fixing compile errors from duplicate asParameter implementations.

• Bug Fixes
  • Added {{^isNumeric}} guard so numeric enums (type: number) don't conform to ParameterConvertible.
  • Covers all number types, not just double (previously only checked isDouble).
  • Updated modelEnum.mustache and modelInlineEnumDeclaration.mustache.

^{Written for commit fa30fa5. Summary will update on new commits.}