fix(query): replace {MODEL} in cast error messages from update and bulkWrite() casting

[SulimanAbdulrazzaq]

Summary

{MODEL} in a custom cast error message is replaced when casting query filters, on document validation (#16480) and in castObject() (#16502), but not when casting updates. updateOne(), updateMany() and findOneAndUpdate() report the literal {MODEL}, and the default cast error message for updates leaves out the for model "..." suffix that filter cast errors have. bulkWrite() has the same gap for both its update and filter casting, since it calls castUpdate() and cast() directly instead of going through Query.

This PR:

• sets the model on cast errors in castUpdate()'s _appendError(), which every update cast error goes through. It's done before the error is thrown or added to the multipleCastError ValidationError, so the aggregated error message is also correct. The context there is the Query, or the model itself for bulkWrite().
• casts bulkWrite() filters through a small helper that sets the model on cast errors, like Query.prototype._castConditions() does.

Examples

const schema = new Schema({
  age: { type: Number, cast: '{VALUE} is not a valid number for model {MODEL}' }
});
const Test = mongoose.model('Test', schema);

await Test.updateOne({}, { age: 'twenty' });
// Before: CastError: "twenty" is not a valid number for model {MODEL}
// After:  CastError: "twenty" is not a valid number for model Test

Added a test in test/schema.test.js next to the other {MODEL} tests. It covers updateOne(), updateMany(), findOneAndUpdate(), multipleCastError, and bulkWrite() updates and filters.

[Copilot]

Copilot review overview

🟡 Changes recommended

Some update paths bypass the new handling, and discriminator updates can report the wrong model.

Get a fresh assessment by requesting another Copilot review.

Review effort: Balanced
Findings: 1

Open (1)

• Ensure all castUpdate errors include the resolved model name · New

What changed in this PR

Adds model-aware formatting to update and bulkWrite() cast errors.

Changes:

• Assigns models to update cast errors.
• Adds model-aware bulk-write filter casting.
• Tests query and bulk-write error messages.

File	Description
lib/​helpers/​query/​castUpdate.js	Sets models on collected update cast errors.
lib/​helpers/​model/​castBulkWrite.js	Wraps bulk-write filter casting.
test/​schema.test.js	Tests {MODEL} substitution.

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