feat(NODE-6329): client bulk write happy path

[durran]

Description

Implements the "happy path" for the new client bulk write in 8.0

What is changing?

• Fixes issue in document sequence serialization to account properly for cstring names and the document length.
• Adds handling of bulk write document sequences in command monitoring.
• Adds a new client bulk write cursor response to handle top level metadata.
• Adds a new client bulk write cursor that is always exhausted when used.
• Implements MongoClient#bulkWrite and all associated model and return types.
• Fixes the command builder to handle comments and collations on updates properly.
• Adds _id generation to inserts in the command builder.
• Handles both acknowledged and unacknowledged client bulk writes.
• Implements client bulk write in the unified runner and runs happy path unified tests.

Is there new documentation needed for these changes?

None. Note release note highlights will be added on last ticket.

What is the motivation for this change?

NODE-6329

Double check the following

• Ran npm run check:lint script
• Self-review completed using the steps outlined here
• PR title follows the correct format: type(NODE-xxxx)[!]: description
  • Example: feat(NODE-1234)!: rewriting everything in coffeescript
• Changes are covered by tests
• New TODOs have a related JIRA ticket

[nbbeeken]

LGTM

[baileympearson]

two small comments

[nbbeeken]

There's a small lint failure, we need to add the cursor to the list of public APIs. Quick question about didUpsert too

[durran]

There's a small lint failure, we need to add the cursor to the list of public APIs. Quick question about didUpsert too

Yes that's fixed in the PR now.