Add support for syncing CCM resources (Cost Allocation Rules, Tag Pipelines)

Start by comparing the existing dashboard, monitor, and logs-pipeline sync implementations and how they use the diff/dependency workflow. Review the Datadog endpoints /api/v2/cost/allocation/rules and /api/v2/tags/enrichment, then define support for the two listed resource types. Done means both resources can be replicated between organizations through the CLI.

Feature request

Currently datadog-sync-cli does not support syncing Cloud Cost Management (CCM) configuration resources across organizations. This includes:

• Custom Allocation Rules (/api/v2/cost/allocation/rules or equivalent)
• Tag Pipeline Rulesets (/api/v2/tags/enrichment)
• Possibly other CCM artifacts (e.g. cost budgets, cost tag configurations)

Use case

As a Technical Account Manager managing multi-org enterprise customers (parent/child org structures), I regularly need to replicate CCM configuration — Allocation Rules and Tag Pipelines — from a source org to one or more destination orgs. Today this has to be done manually via the API, resource by resource, which does not scale well across many child orgs and is error-prone compared to the diff/sync workflow the tool already provides for other resource types (dashboards, monitors, logs pipelines, etc.).

Proposed resources

Both are manageable via Terraform today (datadog_cloud_cost_management_* resources), so the underlying CRUD semantics should already be well defined.

Alternative considered

Doing this via direct API calls per organization — works but doesn't scale for TAMs managing many child orgs, and loses the diff/dependency-tracking benefits datadog-sync provides for other resource types.

Happy to provide more context or test against a real multi-org customer setup if useful.