Add support for glue schemas and registries

[joshAtRula]

Issue #, if available: N/A

Description of changes: This PR adds support to the controller for managing Registries and Schemas.

Testing & Documentation for AWS Glue Schema Controller

This PR adds comprehensive testing infrastructure and documentation examples for the AWS Glue Schema controller resource.

Changes

Test Coverage Added

Unit Tests (pkg/resource/schema/schema_test.go)

• 18 unit tests covering CRUD operations, status conditions, and error handling
• Validates resource lifecycle management and field operations

Integration Tests (test/integration/schema_integration_test.go)

• 13 integration tests with mock AWS Glue API
• Tests create, read, update, delete operations with actual API interactions
• Validates registry references, compatibility modes, and data formats (AVRO, JSON, Protobuf)

End-to-End Tests (test/e2e/schema_e2e_test.go)

• 13 E2E tests covering complete resource lifecycle
• Tests multi-resource scenarios, concurrent operations, and cleanup
• Validates registry integration and schema evolution

Validation Tests (pkg/resource/schema/validation_test.go)

• 44 validation tests ensuring field constraints and business rules
• Covers required fields, enum validation, format validation, cross-field validation
• Tests compatibility modes, data formats, naming conventions, and tags

Documentation Tests (pkg/resource/schema/documentation_test.go)

• 10 test categories validating example accuracy and API coverage
• Tests all 7 compatibility modes and 3 data formats
• Validates example YAML files match current API structure

Documentation & Examples

Test Documentation (test/documentation/README.md)

• Comprehensive guide for running and extending documentation tests
• Explains test categories and validation levels

Example YAML Manifests (examples/)

• schema-basic.yaml - Basic AVRO schema
• schema-with-registry.yaml - Schema with registry reference
• schema-json.yaml - JSON Schema format
• schema-protobuf.yaml - Protobuf format
• schema-complex.yaml - Complex nested structures

Test Results

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[ack-prow]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: joshAtRula
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[ack-prow]

Hi @joshAtRula. Thanks for your PR.

I'm waiting for a aws-controllers-k8s member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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