RUBY-3611 Support $lookup in CSFLE/QE

[jamis]

Adds support for $lookup with CSFLE and QE.

[Copilot]

Pull request overview

Adds driver + test support for running CSFLE/QE aggregation pipelines that include $lookup, which requires libmongocrypt to handle multiple collection schemas and (for some operations) to request collection info for a specific database.

Changes:

• Enable/handle new libmongocrypt capabilities: multiple-collection collinfo, and the need_mongo_collinfo_with_db context state.
• Update encryption I/O to return all matching collection info documents (not just the first) and feed each to libmongocrypt.
• Add a new prose integration spec and supporting schema/key fixtures to validate $lookup behavior across CSFLE/QE/plain collections.

Reviewed changes

Copilot reviewed 17 out of 17 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
spec/support/spec_config.rb	Grants test user privileges for the new collection_info_test database used by specs.
spec/support/crypt.rb	Extracts shared extra_options builder into Crypt.extra_options and reuses it in shared FLE helpers.
spec/support/crypt/lookup/schema-qe2.json	Adds QE2 encryptedFields fixture for $lookup prose test.
spec/support/crypt/lookup/schema-qe.json	Adds QE encryptedFields fixture for $lookup prose test.
spec/support/crypt/lookup/schema-non-csfle.json	Adds non-CSFLE JSON schema fixture for prose test case 10.
spec/support/crypt/lookup/schema-csfle2.json	Adds CSFLE2 JSON schema fixture for prose test.
spec/support/crypt/lookup/schema-csfle.json	Adds CSFLE JSON schema fixture for prose test.
spec/support/crypt/lookup/key-doc.json	Adds data key fixture used by the $lookup prose test.
spec/mongo/crypt/handle_spec.rb	Verifies the handle enables new libmongocrypt options.
spec/mongo/crypt/encryption_io_spec.rb	Adds unit coverage ensuring collection_info returns arrays correctly.
spec/mongo/crypt/binding/mongocrypt_spec.rb	Adds unit coverage for new binding option setters.
spec/mongo/crypt/binding/context_spec.rb	Adds coverage for the new context-state enum value.
spec/integration/client_side_encryption/lookup_prose_spec.rb	New prose integration spec validating $lookup behavior for CSFLE and QE.
lib/mongo/crypt/handle.rb	Enables multiple collinfo and “collinfo-with-db” state handling on handle initialization.
lib/mongo/crypt/encryption_io.rb	Changes collection_info to return all matching collection info documents.
lib/mongo/crypt/context.rb	Adds support for the new :need_mongo_collinfo_with_db state and feeds multiple collinfo docs.
lib/mongo/crypt/binding.rb	Extends ctx-state enum and binds new libmongocrypt APIs for $lookup support.

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