Exp: Pull examples from object schema props

[RobinTail]

When describing examples of the IO schemas only top level calls of .example() method used to be taken into account in the generated Documentation

factory.build({
  input: z
    .object({
      key: z.string().nonempty(),
    })
    .example({
      key: "1234-5678-90",
    }),
})

This feature enabled pulling examples up from the shape of object schema properties, so the syntax can be simplified:

factory.build({
  input: z.object({
    key: z.string().nonempty().example("1234-5678-90"),
  }),
})

[coveralls-official]

coverage: 100.0%. remained the same
when pulling 61b7ed7 on exp-proxy-object-prop-examples
into 85e5f54 on master.

[RobinTail]

I want to revisit the composition of the established workflow involved into depicting examples in the generated documentation:

• getFinalEndpointInputSchema
• extractObjectSchema
• getExamples

Perhaps something here should be simplified

[RobinTail]

• getFinalEndpointInputSchema
• extractObjectSchema
• getExamples
  Perhaps something here should be simplified

Reviewed. Once again, it can be simplified but for input flow only (moving copyMeta from getFinalEndpointInputSchema and the pulling from getExamples into extractObjectSchema).
The response part does not go through extractObjectSchema, because it can be not object-based.
The approach also complicates extractObjectSchema significantly.