types(schema): use user-provided THydratedDocumentType as context for virtual get() and set()

[vkarpov15]

Fix #15516

Summary

Quick fix: should use user-specified THydratedDocumentType

Examples

[Copilot]

Pull Request Overview

This PR ensures that user-specified THydratedDocumentType is correctly applied as the this context for virtual getters and setters in Schema.

• Added a new test function gh15516 in schema.test.ts
• Expanded Schema generics to include a custom HydratedUserDoc type
• Asserts that this inside the virtual getter is correctly typed

Comments suppressed due to low confidence (1)

test/types/schema.test.ts:1854

• The test only covers the virtual getter; consider adding a corresponding assertion for the virtual setter to ensure the this context is also correctly typed when setting the virtual property.

  schema.virtual('myVirtual').get(function () {

[hasezoey]

LGTM, aside from lint and types test not running due to it.