Add destinations api client

[charcey]

Proposed Changes:

For inclusion in changelog (if applicable):

1. Added sync and async clients for new Destinations API, added destinations CLI.

Diff of User Interface

Old behavior: N/A

New behavior:
Users can interact with the Destinations API via python client or CLI. Tests added. CLI tutorial added.

PR Checklist:

• This PR is as small and focused as possible
• If this PR includes proposed changes for inclusion in the changelog, the title of this PR summarizes those changes and is ready for inclusion in the Changelog.
• I have updated docstrings for function changes and docs in the 'docs' folder for user interface / behavior changes
• This PR does not break any examples or I have updated them

(Optional) @mentions for Notifications:

[carl-adams-planet]

Linting aside, do we want to target this to main-3.0-dev, since we plan on releasing 3.0 next week?

Selfishly, I want carrots of new features in 3.0 and not just the stick I brought of the disruption of new OAuth mechanisms.

[Copilot]

Pull Request Overview

This PR adds comprehensive support for the new Destinations API by implementing both synchronous and asynchronous client libraries, along with a complete CLI interface. The implementation enables users to create, list, update, and manage destinations for data delivery across various cloud storage providers including Amazon S3, Google Cloud Storage, Azure Blob Storage, and Oracle Cloud Storage.

Key changes include:

• Added async DestinationsClient and sync DestinationsAPI classes with full CRUD operations
• Implemented comprehensive CLI commands for destination management with provider-specific subcommands
• Extended existing Orders and Subscriptions APIs to support destination filtering

Reviewed Changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
planet/clients/destinations.py	New async client implementing core Destinations API operations
planet/sync/destinations.py	Synchronous wrapper for the destinations client
planet/cli/destinations.py	Complete CLI interface with create, list, update, and archive commands
planet/clients/orders.py	Added destination_ref filtering parameter
planet/clients/subscriptions.py	Added destination_ref filtering parameter
tests/integration/test_destinations_api.py	Integration tests covering all client operations
docs/cli/cli-destinations.md	Comprehensive tutorial for CLI usage

[asonnenschein]

LGTM! Let's get this merged to main and deployed with v2, and synced with main-3.0-dev.