New data sources: google_discovery_engine_data_store(s)

[mahdilamb]

Wrote this using Claude to add discoveryengine datastores. Tried to follow the style of google_storage_bucket(s), but to cover a few more use cases. I have reviewed the generated code myself.

Fixes hashicorp/terraform-provider-google#26375

Add two new handwritten data sources for Discovery Engine data stores:

• google_discovery_engine_data_store (singular) — Look up a single data store by data_store_id or display_name. When looking up by display name, lists all stores and returns an error if zero or multiple matches are found.
• google_discovery_engine_data_stores (plural) — List all data stores in a given project and location.

Both data sources:

• Default location to "global" and inherit project from the provider if not set
• Support regional endpoints automatically via {{DiscoveryEngineBasePath}}
• Include acceptance tests and documentation

Files added/modified

• data_source_discovery_engine_data_store.go — singular data source
• data_source_discovery_engine_data_stores.go — plural data source
• data_source_discovery_engine_data_store_test.go — singular acceptance test (by ID + by display_name)
• data_source_discovery_engine_data_stores_test.go — plural acceptance test
• discovery_engine_data_store.html.markdown — singular docs
• discovery_engine_data_stores.html.markdown — plural docs
• provider_mmv1_resources.go.tmpl — register both data sources

Generated with Claude Code (Claude Opus 4.6)

Added `google_discovery_engine_data_store` data source for reading a single Discovery Engine data store by ID or display name

Added `google_discovery_engine_data_stores` data source for listing all Discovery Engine data stores in a project and location

[google-cla]

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[github-actions]

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