fix: Ignore FDv2 objects with unrecognized kinds

[kinyoklion]

Summary

FDv2 SDKs must silently ignore objects of kinds they do not support, so new kinds can be added to payloads without breaking existing SDKs. PutObject.from_dict and DeleteObject.from_dict converted kind with ObjectKind(kind), which raises for anything other than flag or segment: streaming treated the event as malformed and restarted the stream, and polling failed the whole payload. The streaming and polling parsers now skip put-object and delete-object events with an unsupported kind (debug log) before parsing them. A missing kind is still malformed, and known kinds are unchanged. The async data sources share these parsers.

Tests

test_ignores_objects_with_unknown_kinds in the streaming synchronizer and polling payload parsing tests mixes unknown-kind puts and deletes with known objects and checks the payload completes with only the known changes (both failed before the change). Full suite 1772 passed / 367 skipped; mypy, isort, pycodestyle clean.

SDK-3339

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Note

Overview
FDv2 polling and streaming now ignore put-object and delete-object events whose kind is not in this SDK’s supported set, instead of treating them as malformed data.

Previously, PutObject.from_dict / DeleteObject.from_dict called ObjectKind(kind), which raised on future kinds—polling could fail the entire payload and streaming could error and restart. A shared has_unsupported_kind helper in protocolv2 gates parsing; unsupported events are skipped with a debug log while known flag / segment handling is unchanged. Payloads with a missing kind still fail validation.

Tests cover mixed unknown and known kinds for both polling payload parsing and the streaming synchronizer.

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