`graphql-codegen-client-preset`: support configurable document/fragment variable suffixes

[m-sanders]

The plugin hardcodes "Document" and "FragmentDoc" when generating import identifiers for operations and fragments.

This means if you set documentVariableSuffix: '' in your codegen config (a supported option), the plugin generates mismatched imports - it looks for GetUserDocument but codegen exports GetUser.

The upstream codegen has several options that affect variable names:

• documentVariablePrefix / documentVariableSuffix
• fragmentVariablePrefix / fragmentVariableSuffix
• dedupeOperationSuffix
• omitOperationSuffix

None of these are currently configurable in the SWC plugin.

I have a PR ready that adds all six options with backwards-compatible defaults.