[P1.5-S6-ARI-41] `gcp.resource_types` registry in `conf.yaml` + config loader

[bjridicodes]

Ticket: P1.5-S6-03

Type: Feature | Est: 0.5d

Goal: Operators add new GCP service types by editing conf.yaml — no Python required.

Scope:

• conf_template.yaml: add gcp.resource_types section:

  gcp:
    resource_types:
      cloud_dataproc_cluster:
        - 'resource.type="cloud_dataproc_cluster"'
      cloud_dataproc_job:
        - 'resource.type="cloud_dataproc_job"'
      bigquery_dataset:
        - 'resource.type="bigquery_dataset"'
        - 'protoPayload.serviceName="bigquery.googleapis.com"'
      cloud_function:
        - 'resource.type="cloud_function"'
      pubsub_subscription:
        - 'resource.type="pubsub_subscription"'
      gcs_bucket:
        - 'resource.type="gcs_bucket"'
      cloud_run_revision:
        - 'resource.type="cloud_run_revision"'
      composer_environment:
        - 'resource.type="composer_environment"'

• core/config.py: gcp_resource_type_templates() -> dict[str, list[str]] — reads gcp.resource_types from loaded conf; returns {} if absent

Acceptance criteria:

• conf_template.yaml has all 8 resource types with correct Cloud Logging filter syntax
• gcp_resource_type_templates() returns the dict when conf.yaml is populated
• gcp_resource_type_templates() returns {} when gcp.resource_types is absent (no exception)