feat: support passing product data with createProduct and createProductVariant

[aldeed]

Resolves #6103
Type: feature

Changes

• Add optional ProductInput to createProduct mutation
• Add a createProduct mutation param to allow skipping auto-creation of the first variant
• Add optional ProductVariantInput to createProductVariant mutation

Breaking changes

None

Testing

1. Pass product param to createProduct mutation with all available fields set, and verify that they have correct values in the response and the database.
2. Pass variant param to createProductVariant mutation with all available fields set, and verify that they have correct values in the response and the database.
3. Ensure that updateProduct and updateProductVariant mutations still work correctly for updating the same fields.
4. Pass shouldCreateFirstVariant: false when calling the createProduct mutation, and verify that the variants array is empty in the response, and that no variant was created in the database.

[mikemurray]

@aldeed I can create variants with a price but not compareAtPrice. I thought prices should be set through updateVariantPrices mutation rather than through the main variant mutations. Not sure if we should remove the prices field, add compareAtPrice, or just leave it as is.

Otherwise, things seem to work fine.

[brent-hoover]

@aldeed I think we should allow (optional) passing of _id when creating a product via the API. This would allow import processes that want to use a natural key to specify this. If not specified then it could use the typical random string.

[aldeed]

@zenweasel Added setting _id on creation for products and variants

@mikemurray This is an existing issue so I cannot remove price without it being a breaking change to the updateProductVariant mutation. Instead, I added compareAtPrice to keep it consistent, but marked both of those fields as deprecated with instructions to use updateProductVariantPrices instead.

@manueldelreal This should be ready for final testing now.

[manueldelreal]