Add identityType, effectiveIdentity, and default_from_api to Vertex A…

[mmontan]

Add identityType, effectiveIdentity, and default_from_api to google_vertex_ai_reasoning_engine (beta)

This PR adds two new beta fields to the spec block of google_vertex_ai_reasoning_engine:

• identity_type (beta): Specifies the identity type to use for the Reasoning Engine. Accepts SERVICE_ACCOUNT (uses a custom service account if set, otherwise the default Vertex AI Reasoning Engine Service Agent) or AGENT_IDENTITY (uses Agent Identity; service_account must not be set).
• effective_identity (beta, output-only): Reports the effective identity in use for the Reasoning Engine.

Additionally, default_from_api: true is added to the spec field to allow the API to populate defaults, as effective_identity is an output field computed server-side.

An acceptance test (TestAccVertexAIReasoningEngine_vertexAiReasoningEngineIdentityTypeUpdate) is included to verify updating between SERVICE_ACCOUNT and AGENT_IDENTITY identity types using the beta provider.

Fixed hashicorp/terraform-provider-google#26376
Fixed hashicorp/terraform-provider-google#25101

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Release Note Template for Downstream PRs (will be copied)

vertexai: added `spec.identity_type` and `spec.effective_identity` fields to `google_vertex_ai_reasoning_engine` resource (beta)

[github-actions]

Googlers: For automatic test runs see go/terraform-auto-test-runs.

@zli82016, a repository maintainer, has been assigned to review your changes. If you have not received review feedback within 2 business days, please leave a comment on this PR asking them to take a look.

You can help make sure that review is quick by doing a self-review and by running impacted tests locally.

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 3 files changed, 77 insertions(+))
google-beta provider: Diff ( 4 files changed, 129 insertions(+))
terraform-google-conversion: Diff ( 1 file changed, 22 insertions(+))

[modular-magician]

Tests analytics

Total tests: 85
Passed tests: 81
Skipped tests: 3
Affected tests: 1

Click here to see the affected service packages

• vertexai

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

• TestAccVertexAIReasoningEngine_vertexAiReasoningEngineSourceUpdate

Get to know how VCR tests work

[modular-magician]

🟢 Tests passed during RECORDING mode:
TestAccVertexAIReasoningEngine_vertexAiReasoningEngineSourceUpdate [Debug log]

🟢 No issues found for passed tests after REPLAYING rerun.

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🟢 All tests passed!

View the build log or the debug log for each test

[zli82016]

api_name: 'identityType' is not needed, as the api_name will be identityType by default.

[zli82016]

api_name is not needed

[zli82016]

context with the field random_suffix should be passed to the function.

Example: https://github.com/hashicorp/terraform-provider-google-beta/blob/9120405b72eb6989ae66ff4303e4f801dd8c1b10/google-beta/services/vertexai/resource_vertex_ai_reasoning_engine_generated_test.go#L91

[zli82016]

Suggested change

	display_name = "sample-reasoning-engine"
	display_name = "tf-test-sample-reasoning-engine%{random_suffix}"

[zli82016]

Suggested change

	display_name = "sample-reasoning-engine"
	display_name = "tf-test-sample-reasoning-engine%{random_suffix}"