KIP-1146 — Anchored punctuation

Accepted Kafka 4.2 Streams

Adds anchored (wall-clock-aligned) punctuation to Kafka Streams so that periodic callbacks can be triggered at fixed calendar intervals (e.g., every hour at HH:00:00) regardless of when the punctuation was registered. Existing wall-clock punctuation starts its interval from registration time, producing non-deterministic trigger offsets relative to wall clock, which caused complex workarounds for time-aligned processing in sectors like energy grid balancing.

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