* PHPC-2495, PHPC-2490, PHPC-2491, PHPC-2492: BulkWriteCommand ctor and ops

* PHPC-2494: BulkWriteCommandResult and BulkWriteCommandException

It was possible to reuse WriteConcernError and WriteError with slight changes to their init functions.

* Include missing header in WriteResult.h

This was not necessary for compilation, but it makes the header internally consistent.

* PHPC-2493: Manager and Server::executeBulkWriteCommand()

* PHPC-2494: Handle null error fields in BulkWriteCommandResult

Always return arrays for writeErrors and writeConcernErrors

* PHPC-2494: Return writeErrors as an associative array

* PHPC-2493: Revise error handling for mongoc_bulkwrite_execute

* Consistent WriteError and WriteConcernError parsing for bulk write results

* BulkWriteCommand tests

* clang-format

* Remove BulkWriteCommandResult::getServer()

Per CDRIVER-5843, libmongoc does not consistently populate this field. It also isn't required by the spec, so omit it for now.

* Check for _id extraction before appending insert

* Regenerate BulkWriteCommandException arginfo

* PHPC-2493: Relocate writeConcern option to executeBulkWriteCommand()

* Parse sort option for replaceOne and updateOne

* BulkWriteCommand::replaceOne() need not accept root-level arrays

* Preserve empty documents for verbose results and error reply

Result maps should only be null if verboseResults=false. Additionally, the error reply document can default to an empty document on error (as it is in libmongoc).

* PHPC-2494: Relocate error fields to BulkWriteCommandException

Revise the stubs to reflect that executeBulkWriteCommand() always returns a BulkWriteCommandResult. If the result is unacknowledged, that is reported via isAcknowledged() and other methods can throw, which is consistent with WriteResult for the legacy bulk write API.

If the result is empty on error (i.e. no writes were successful), BulkWriteCommandException::$partialResult is left unset.

* Throw BulkWriteCommandException directly for server errors

This also ensures that BulkWriteCommandException uses the original server-side error code and message (if available) for top-level errors.

* Check for empty error_reply instead of NULL

mongoc_bulkwriteexception_errorreply() always returns an initialized document, but it may be empty. This ensures that an InvalidArgumentException is not unnecessarily proxied behind a BulkWriteCommandException.

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