fix: Ignore FDv2 put-object and delete-object events with unsupported 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. The protocol handler checked the kind on put-object (with a warning per object) but not on delete-object, so an unknown-kind delete reached the server payload listener: the in-memory store kept it under an unknown namespace, and the persistent store wrapper threw in sortDataSet during init, leaving the store unavailable. Put-object and delete-object now drop kinds without a registered processor at debug level. The check is an own-property lookup, so kinds such as constructor or __proto__ no longer resolve to inherited object members. A supported kind whose processor rejects the object still warns.

Tests

protocolHandler.test.ts covers unknown puts and deletes mixed with known objects, built-in member names as kinds, and the known-kind rejection warning; PollingProcessorFDv2.test.ts (server) and StreamingFDv2Base.test.ts (client) check only known updates are delivered with no warnings. common 642/642, sdk-server 1551 passed / 7 skipped, sdk-client 874/874; oxlint and oxfmt clean.

SDK-3341. Covers the delete-object and sortDataSet items of SDK-3086; its remaining persistence hardening is not part of this change.

---

Note

Overview
FDv2 protocol handling now treats unknown object kinds the same on put-object and delete-object: events whose kind has no registered processor are dropped at debug (not warn), so future payload kinds do not break older SDKs or poll into the data store.

Supported-kind filtering uses an own-property check on objProcessors, so kinds like constructor or __proto__ no longer match inherited object members. Rejection by a processor for a known kind still warns and drops the object.

Tests cover mixed supported/unsupported streams, inherited member names, processor rejection, and end-to-end streaming/polling paths (only known updates delivered, no warn/error logs).

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@launchdarkly/js-client-sdk-common size report
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