docs: document open_tracking suppression type

[rafaelmatsumotomb]

Summary

Documents the new open_tracking suppression type in the Suppression List API docs (tracking-consent revocation — knowledge-base #43, live in production).

Covered:

• New entry kind in the intro, with its key semantic: it does not block sending — mail delivers normally, but no open events are generated (pixel still served)
• open_tracking added to every type/types enum (suppression object, bulk PUT, single PUT, retrieve, delete, search)
• New source Tracking Consent Revoked
• list_id not supported for the type (with the 400 example), and the updated "Type must be one of" error text
• The read/delete default: untyped operations touch only transactional/non_transactional — open_tracking entries must be requested explicitly

🤖 Generated with Claude Code

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Note

Low Risk
Documentation-only changes to the API blueprint with no runtime or security impact.

Overview
Documents the open_tracking suppression type in the Suppression List API reference, for recipients who revoke open-tracking consent.

The intro clarifies that open_tracking does not block delivery—mail sends as usual, but no open events are recorded (the pixel is still served). open_tracking is added to all relevant type/types enums (object, bulk/single PUT, retrieve, delete, search), along with source Tracking Consent Revoked. list_id is documented as unsupported for this type (always account-wide), including a new 400 example and updated allowed-type error text.

Read and delete defaults are spelled out: without types/type, only transactional and non_transactional entries are returned or removed; open_tracking must be requested explicitly.

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